{"title":"Freshwater Anodes","description":"\u003cp\u003eAnodes for fresh water. \u003cstrong\u003eMagnesium to ASTM B843\u003c\/strong\u003e is the fresh-water alloy; zinc is the wrong choice and will passivate. Where zinc is required in fresh or buried service, it must be \u003cstrong\u003eASTM B418 Type II\u003c\/strong\u003e, the high-purity grade, not the Type I seawater alloy.\u003c\/p\u003e","products":[{"product_id":"shaft-anodes","title":"Propeller Shaft Anodes — Streamlined Collar","description":"\u003ch2\u003ePropeller Shaft Anodes — Streamlined Collar\u003c\/h2\u003e\n\u003cp\u003eTwo-piece streamlined collar anodes that clamp directly to the propeller\nshaft, in \u003cstrong\u003e31 sizes from 1\/2 in to 6 in and 25 mm to 60 mm\u003c\/strong\u003e.\nAvailable in zinc, aluminium or magnesium — tell us the water and we will quote\nthe right alloy.\u003c\/p\u003e\n\n\u003ch3\u003eImperial shafts\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eShaft diameter\u003c\/th\u003e\n\u003cth\u003eEquivalent\u003c\/th\u003e\n\u003cth\u003eTypical weight\u003c\/th\u003e\n\u003cth\u003eCommon reference\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1\/2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e12.7 mm\u003c\/td\u003e\n\u003ctd\u003e0.23 kg (0.51 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX00\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e3\/4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e19.05 mm\u003c\/td\u003e\n\u003ctd\u003e0.38 kg (0.84 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX01\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e7\/8 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e22.23 mm\u003c\/td\u003e\n\u003ctd\u003e0.43 kg (0.95 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX02\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e25.4 mm\u003c\/td\u003e\n\u003ctd\u003e0.45 kg (0.99 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX03\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1-1\/8 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e28.58 mm\u003c\/td\u003e\n\u003ctd\u003e0.52 kg (1.15 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX04\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1-1\/4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e31.75 mm\u003c\/td\u003e\n\u003ctd\u003e0.53 kg (1.17 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX05\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e1-1\/4 in\u003c\/strong\u003e (extra heavy)\u003c\/td\u003e\n\u003ctd\u003e31.75 mm\u003c\/td\u003e\n\u003ctd\u003e0.79 kg (1.74 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX05A\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1-3\/8 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e34.93 mm\u003c\/td\u003e\n\u003ctd\u003e0.67 kg (1.48 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX06\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1-1\/2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e38.1 mm\u003c\/td\u003e\n\u003ctd\u003e0.76 kg (1.68 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX07\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e1-3\/4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e44.45 mm\u003c\/td\u003e\n\u003ctd\u003e1.13 kg (2.49 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX08\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e50.8 mm\u003c\/td\u003e\n\u003ctd\u003e1.41 kg (3.11 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX09\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e2-1\/4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e57.15 mm\u003c\/td\u003e\n\u003ctd\u003e2.76 kg (6.08 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX10\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e2-1\/2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e63.5 mm\u003c\/td\u003e\n\u003ctd\u003e2.35 kg (5.18 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX11\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e2-3\/4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e69.85 mm\u003c\/td\u003e\n\u003ctd\u003e3.42 kg (7.54 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX12\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e3 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e76.2 mm\u003c\/td\u003e\n\u003ctd\u003e2.97 kg (6.55 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX13\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e3-1\/4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e82.55 mm\u003c\/td\u003e\n\u003ctd\u003e3.27 kg (7.21 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX14Z\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e3-1\/2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e88.9 mm\u003c\/td\u003e\n\u003ctd\u003e4.10 kg (9.04 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX15\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e4 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e101.6 mm\u003c\/td\u003e\n\u003ctd\u003e4.04 kg (8.91 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX17\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e4-1\/2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e114.3 mm\u003c\/td\u003e\n\u003ctd\u003e5.63 kg (12.41 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX18\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e5 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e127 mm\u003c\/td\u003e\n\u003ctd\u003e4.20 kg (9.26 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX19\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e5-1\/2 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e139.7 mm\u003c\/td\u003e\n\u003ctd\u003e7.24 kg (15.96 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX20\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e6 in\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e152.4 mm\u003c\/td\u003e\n\u003ctd\u003e5.44 kg (11.99 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX21\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eMetric shafts\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eShaft diameter\u003c\/th\u003e\n\u003cth\u003eEquivalent\u003c\/th\u003e\n\u003cth\u003eTypical weight\u003c\/th\u003e\n\u003cth\u003eCommon reference\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e25 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.984 in\u003c\/td\u003e\n\u003ctd\u003e0.549 kg (1.21 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX25\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e28 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.102 in\u003c\/td\u003e\n\u003ctd\u003e0.581 kg (1.28 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX28Z\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e30 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.181 in\u003c\/td\u003e\n\u003ctd\u003e0.558 kg (1.23 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX30\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e35 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.378 in\u003c\/td\u003e\n\u003ctd\u003e0.730 kg (1.61 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX35\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e40 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.575 in\u003c\/td\u003e\n\u003ctd\u003e1.429 kg (3.15 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX40\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e45 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.772 in\u003c\/td\u003e\n\u003ctd\u003e1.261 kg (2.78 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX45\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e50 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.969 in\u003c\/td\u003e\n\u003ctd\u003e1.075 kg (2.37 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX50\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e55 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2.165 in\u003c\/td\u003e\n\u003ctd\u003e2.735 kg (6.03 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX55\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e60 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2.362 in\u003c\/td\u003e\n\u003ctd\u003e2.672 kg (5.89 lb)\u003c\/td\u003e\n\u003ctd\u003eCMX60\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cp\u003e\u003cem\u003eThe anode is sized by the shaft it clamps to, so each size is listed in\nthe shaft's own unit with the equivalent alongside. Measure the shaft, do not\nmeasure the old anode — a half-wasted anode reads undersize. Weights are typical\nfor the streamlined profile and are confirmed at quotation.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eGot an old part number?\u003c\/h3\u003e\n\u003cp\u003eThe reference column above is the number most commonly cast into this style of\nanode. If the number on the one you removed is not there, send us a photo of it\nand the shaft diameter and we will match it — most aftermarket numbering\ndescends from the same US military specification, so nearly everything\ncross-references.\u003c\/p\u003e\n\n\u003ch3\u003eWhich alloy\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctr\u003e\n\u003cth\u003eZinc\u003c\/th\u003e\n\u003ctd\u003eSalt water. To \u003cstrong\u003eASTM B418 Type I\u003c\/strong\u003e — the alloyed\n    seawater grade, whose composition also meets \u003cstrong\u003eMIL-A-18001K\u003c\/strong\u003e.\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eAluminium\u003c\/th\u003e\n\u003ctd\u003eSalt and brackish water. Al-Zn-In alloy; longer life\n    per kilogram and now the default on new offshore work.\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eMagnesium\u003c\/th\u003e\n\u003ctd\u003eFresh water only, to \u003cstrong\u003eASTM B843\u003c\/strong\u003e. Never\n    use it as a saltwater substitute — it wastes in months.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003cp\u003eFor fresh water and buried service in zinc, \u003cstrong\u003eASTM B418 Type II\u003c\/strong\u003e is\nthe high-purity grade. Tell us the water and we will quote the right alloy rather\nthan assume.\u003c\/p\u003e\n\n\u003ch3\u003eSizing\u003c\/h3\u003e\n\u003cp\u003eThe material specs say nothing about how much anode to fit. That comes from\n\u003cstrong\u003eABYC E-2\u003c\/strong\u003e for boats and \u003cstrong\u003eDNV-RP-B401\u003c\/strong\u003e for ships and\noffshore structures, which size the anode mass against the area to be protected,\nthe current density and the design life.\u003c\/p\u003e\n\u003cp\u003eWhatever the calculation says, the maintenance rule is the same:\n\u003cstrong\u003ereplace at about 50% wasted.\u003c\/strong\u003e A half-wasted anode is not a\nhalf-working anode — output falls away as surface area is lost, so the last half\nprotects far less than the first.\u003c\/p\u003e\n\n\u003ch3\u003eWhat to put on your purchase order\u003c\/h3\u003e\n\u003cp\u003eZinc anodes fail by \u003cstrong\u003epassivating\u003c\/strong\u003e — they skin over and stop\nproducing current while still looking perfectly serviceable on the shaft. The\nusual cause is iron contamination, which is exactly what ASTM B418 caps at\n0.005%. Specify \u003cstrong\u003e\"to ASTM B418 Type I, mill certificate with each\nlot\"\u003c\/strong\u003e and you have something to test against. Without it, a cheap anode\nthat does nothing looks identical to a good one until the shaft is pitted.\u003c\/p\u003e\n\u003cp\u003eSee the \u003ca href=\"\/pages\/anodes\"\u003eanode selection guide\u003c\/a\u003e for the full alloy,\nsizing and specification detail.\u003c\/p\u003e","brand":"Dibblee","offers":[{"title":"1\/2 in shaft (12.7 mm)","offer_id":50199364174101,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"3\/4 in shaft (19.05 mm)","offer_id":50199364206869,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"7\/8 in shaft (22.23 mm)","offer_id":50199364239637,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1 in shaft (25.4 mm)","offer_id":50199364272405,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1-1\/8 in shaft (28.58 mm)","offer_id":50199364305173,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1-1\/4 in shaft (31.75 mm)","offer_id":50199364337941,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1-1\/4 in shaft (31.75 mm) — extra heavy","offer_id":50199364370709,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1-3\/8 in shaft (34.93 mm)","offer_id":50199364403477,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1-1\/2 in shaft (38.1 mm)","offer_id":50199364436245,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"1-3\/4 in shaft (44.45 mm)","offer_id":50199364469013,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"2 in shaft (50.8 mm)","offer_id":50199364501781,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"2-1\/4 in shaft (57.15 mm)","offer_id":50199364534549,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"2-1\/2 in shaft (63.5 mm)","offer_id":50199364567317,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"2-3\/4 in shaft (69.85 mm)","offer_id":50199364600085,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"3 in shaft (76.2 mm)","offer_id":50199364632853,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"3-1\/4 in shaft (82.55 mm)","offer_id":50199364665621,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"3-1\/2 in shaft (88.9 mm)","offer_id":50199364698389,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"4 in shaft (101.6 mm)","offer_id":50199364731157,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"4-1\/2 in shaft (114.3 mm)","offer_id":50199364763925,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"5 in shaft (127 mm)","offer_id":50199364796693,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"5-1\/2 in shaft (139.7 mm)","offer_id":50199364829461,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"6 in shaft (152.4 mm)","offer_id":50199364862229,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"25 mm shaft (0.984 in)","offer_id":50199364894997,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"28 mm shaft (1.102 in)","offer_id":50199364927765,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"30 mm shaft (1.181 in)","offer_id":50199364960533,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"35 mm shaft (1.378 in)","offer_id":50199364993301,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"40 mm shaft (1.575 in)","offer_id":50199365026069,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"45 mm shaft (1.772 in)","offer_id":50199365058837,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"50 mm shaft (1.969 in)","offer_id":50199365091605,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"55 mm shaft (2.165 in)","offer_id":50199365124373,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"60 mm shaft (2.362 in)","offer_id":50199365157141,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}]},{"product_id":"magnesium-weld-on-hull-anodes","title":"Magnesium Weld-On Hull Anodes — Freshwater","description":"\u003ch2\u003eMagnesium Weld-On Hull Anodes — Freshwater\u003c\/h2\u003e\n\u003cp\u003eMagnesium hull anodes with steel inserts for welding direct to the hull, for vessels working in fresh water. Four sizes from 1.5 kg to 4.5 kg.\u003c\/p\u003e\n\n\u003ch3\u003eWhy magnesium in fresh water\u003c\/h3\u003e\n\u003cp\u003eFresh water is far more resistive than sea water, and zinc cannot drive enough\ncurrent through it — it polarises, skins over and stops protecting while still\nlooking perfectly serviceable on the hull. \u003cstrong\u003eMagnesium is the fresh-water\nalloy.\u003c\/strong\u003e If your vessel works the Great Lakes, the St Lawrence, or any\ninland waterway, zinc is the wrong metal no matter what the chandlery stocks.\u003c\/p\u003e\n\n\u003ch3\u003eSizes and weights\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSize (L × W × D)\u003c\/th\u003e\n\u003cth\u003eWeight\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e385 × 76 × 32 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(15.2 × 3.0 × 1.26 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e1.5 kg (3.31 lb)\u003c\/td\u003e\n\u003ctd\u003eweld-on bar\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e405 × 152 × 32 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(15.9 × 6.0 × 1.26 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e2.8 kg (6.17 lb)\u003c\/td\u003e\n\u003ctd\u003e—\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e459 × 152 × 32 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(18.1 × 6.0 × 1.26 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e3.5 kg (7.72 lb)\u003c\/td\u003e\n\u003ctd\u003e—\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e563 × 102 × 64 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(22.2 × 4.0 × 2.52 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e4.5 kg (9.92 lb)\u003c\/td\u003e\n\u003ctd\u003edeep section\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eDimensions in millimetres with inches alongside. Weights are nominal and\nconfirmed at quotation.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eAlloy — ASTM B843\u003c\/h3\u003e\n\u003cp\u003eMagnesium anodes are cast to \u003cstrong\u003eASTM B843\u003c\/strong\u003e, which covers two\nalloys, and the choice between them matters more than most people expect:\u003c\/p\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eAlloy\u003c\/th\u003e\n\u003cth\u003eOpen circuit potential\u003c\/th\u003e\n\u003cth\u003eUse\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003eAZ63\u003c\/strong\u003e — standard potential\u003cbr\u003e(Al 5.3–6.7%, Zn 2.5–3.5%, Mn 0.15–0.7%)\u003c\/td\u003e\n        \u003ctd\u003e≈ −1.55 V\u003c\/td\u003e\n        \u003ctd\u003eThe default. Steel and GRP hulls in fresh water, and \u003cstrong\u003ethe right\n        choice near aluminium\u003c\/strong\u003e.\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003eM1C\u003c\/strong\u003e — high potential\u003cbr\u003e(Mn 0.5–1.3%, Fe ≤0.03%, Ni ≤0.001%, Cu ≤0.02%)\u003c\/td\u003e\n        \u003ctd\u003e≈ −1.70 to −1.75 V\u003c\/td\u003e\n        \u003ctd\u003eHigh-resistivity water and soil, where the extra driving voltage is\n        needed to push current.\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eA caution on aluminium\u003c\/h3\u003e\n\u003cp\u003eMore driving voltage is not better. \u003cstrong\u003eAluminium suffers alkali attack and\nhydrogen blistering of its paint when driven more negative than about\n−1200 mV\u003c\/strong\u003e, and high-potential magnesium will do exactly that. On aluminium\nhulls, outdrives and sterndrives use the standard-potential alloy and watch the\nprotection potential. Blistering paint and unusually fast anode wastage are the\nsymptoms of over-protection, not of needing more anode.\u003c\/p\u003e\n\n\u003ch3\u003eHow magnesium compares\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003e\u003c\/th\u003e\n\u003cth\u003eZinc\u003c\/th\u003e\n\u003cth\u003eAluminium\u003c\/th\u003e\n\u003cth\u003eMagnesium\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eWater\u003c\/th\u003e\n\u003ctd\u003eSalt\u003c\/td\u003e\n\u003ctd\u003eSalt and brackish\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eFresh only\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eCapacity\u003c\/th\u003e\n\u003ctd\u003e≈ 780 A·h\/kg\u003c\/td\u003e\n\u003ctd\u003e≈ 2000–2500 A·h\/kg\u003c\/td\u003e\n\u003ctd\u003e≈ 1100 A·h\/kg\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eRelative life, same size\u003c\/th\u003e\n\u003ctd\u003e100\u003c\/td\u003e\n\u003ctd\u003e130–150\u003c\/td\u003e\n\u003ctd\u003e≈ 30\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003ctd\u003eASTM B418\u003c\/td\u003e\n\u003ctd\u003eno composition standard — qualified by test\u003c\/td\u003e\n\u003ctd\u003eASTM B843\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eMagnesium drives harder than either of the others but spends itself doing it —\nroughly a third of the life of zinc for the same size. That is the trade, and it\nis why magnesium belongs in fresh water and nowhere else. Put it in salt and it\nwill waste in a season.\u003c\/p\u003e\n\n\u003ch3\u003eSizing and replacement\u003c\/h3\u003e\n\u003cp\u003eSizing comes from \u003cstrong\u003eABYC E-2\u003c\/strong\u003e for boats and\n\u003cstrong\u003eDNV-RP-B401\u003c\/strong\u003e for ships. Whatever the calculation says,\n\u003cstrong\u003ereplace at about 50% wasted\u003c\/strong\u003e — output falls away as surface area\nis lost.\u003c\/p\u003e\n\u003cp\u003eWrong alloy for your water? See\n\u003ca href=\"\/collections\/saltwater-anodes\"\u003esaltwater anodes\u003c\/a\u003e — zinc to ASTM B418\nType I and aluminium.\u003c\/p\u003e","brand":"Dibblee","offers":[{"title":"385 x 76 x 32 mm bar — 1.5 kg","offer_id":50199409590549,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"405 x 152 x 32 mm — 2.8 kg","offer_id":50199409623317,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"459 x 152 x 32 mm — 3.5 kg","offer_id":50199409656085,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"563 x 102 x 64 mm — 4.5 kg","offer_id":50199409688853,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}]},{"product_id":"magnesium-bolt-on-hull-anodes","title":"Magnesium Bolt-On Hull Anodes — Freshwater","description":"\u003ch2\u003eMagnesium Bolt-On Hull Anodes — Freshwater\u003c\/h2\u003e\n\u003cp\u003eMagnesium hull anodes that bolt on rather than weld, for GRP and for steel hulls where hot work is not wanted. Includes a bolt-on disc and a button anode.\u003c\/p\u003e\n\n\u003ch3\u003eWhy magnesium in fresh water\u003c\/h3\u003e\n\u003cp\u003eFresh water is far more resistive than sea water, and zinc cannot drive enough\ncurrent through it — it polarises, skins over and stops protecting while still\nlooking perfectly serviceable on the hull. \u003cstrong\u003eMagnesium is the fresh-water\nalloy.\u003c\/strong\u003e If your vessel works the Great Lakes, the St Lawrence, or any\ninland waterway, zinc is the wrong metal no matter what the chandlery stocks.\u003c\/p\u003e\n\n\u003ch3\u003eSizes and weights\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSize (L × W × D)\u003c\/th\u003e\n\u003cth\u003eWeight\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e318 × 65 × 32 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(12.5 × 2.6 × 1.26 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e0.7 kg (1.54 lb)\u003c\/td\u003e\n\u003ctd\u003e—\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e457 × 102 × 64 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(18.0 × 4.0 × 2.52 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e3.5 kg (7.72 lb)\u003c\/td\u003e\n\u003ctd\u003edeep section\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e229 × 229 × 25 mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(9.0 × 9.0 × 0.98 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003e2.25 kg (4.96 lb)\u003c\/td\u003e\n\u003ctd\u003ebolt-on disc\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003e140 × 140 × — mm\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003e(5.5 × 5.5 in)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003ctd\u003eon request\u003c\/td\u003e\n\u003ctd\u003ebutton anode\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eDimensions in millimetres with inches alongside. Weights are nominal and\nconfirmed at quotation.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eAlloy — ASTM B843\u003c\/h3\u003e\n\u003cp\u003eMagnesium anodes are cast to \u003cstrong\u003eASTM B843\u003c\/strong\u003e, which covers two\nalloys, and the choice between them matters more than most people expect:\u003c\/p\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eAlloy\u003c\/th\u003e\n\u003cth\u003eOpen circuit potential\u003c\/th\u003e\n\u003cth\u003eUse\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003eAZ63\u003c\/strong\u003e — standard potential\u003cbr\u003e(Al 5.3–6.7%, Zn 2.5–3.5%, Mn 0.15–0.7%)\u003c\/td\u003e\n        \u003ctd\u003e≈ −1.55 V\u003c\/td\u003e\n        \u003ctd\u003eThe default. Steel and GRP hulls in fresh water, and \u003cstrong\u003ethe right\n        choice near aluminium\u003c\/strong\u003e.\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003eM1C\u003c\/strong\u003e — high potential\u003cbr\u003e(Mn 0.5–1.3%, Fe ≤0.03%, Ni ≤0.001%, Cu ≤0.02%)\u003c\/td\u003e\n        \u003ctd\u003e≈ −1.70 to −1.75 V\u003c\/td\u003e\n        \u003ctd\u003eHigh-resistivity water and soil, where the extra driving voltage is\n        needed to push current.\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eA caution on aluminium\u003c\/h3\u003e\n\u003cp\u003eMore driving voltage is not better. \u003cstrong\u003eAluminium suffers alkali attack and\nhydrogen blistering of its paint when driven more negative than about\n−1200 mV\u003c\/strong\u003e, and high-potential magnesium will do exactly that. On aluminium\nhulls, outdrives and sterndrives use the standard-potential alloy and watch the\nprotection potential. Blistering paint and unusually fast anode wastage are the\nsymptoms of over-protection, not of needing more anode.\u003c\/p\u003e\n\n\u003ch3\u003eHow magnesium compares\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003e\u003c\/th\u003e\n\u003cth\u003eZinc\u003c\/th\u003e\n\u003cth\u003eAluminium\u003c\/th\u003e\n\u003cth\u003eMagnesium\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eWater\u003c\/th\u003e\n\u003ctd\u003eSalt\u003c\/td\u003e\n\u003ctd\u003eSalt and brackish\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eFresh only\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eCapacity\u003c\/th\u003e\n\u003ctd\u003e≈ 780 A·h\/kg\u003c\/td\u003e\n\u003ctd\u003e≈ 2000–2500 A·h\/kg\u003c\/td\u003e\n\u003ctd\u003e≈ 1100 A·h\/kg\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eRelative life, same size\u003c\/th\u003e\n\u003ctd\u003e100\u003c\/td\u003e\n\u003ctd\u003e130–150\u003c\/td\u003e\n\u003ctd\u003e≈ 30\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003ctd\u003eASTM B418\u003c\/td\u003e\n\u003ctd\u003eno composition standard — qualified by test\u003c\/td\u003e\n\u003ctd\u003eASTM B843\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eMagnesium drives harder than either of the others but spends itself doing it —\nroughly a third of the life of zinc for the same size. That is the trade, and it\nis why magnesium belongs in fresh water and nowhere else. Put it in salt and it\nwill waste in a season.\u003c\/p\u003e\n\n\u003ch3\u003eSizing and replacement\u003c\/h3\u003e\n\u003cp\u003eSizing comes from \u003cstrong\u003eABYC E-2\u003c\/strong\u003e for boats and\n\u003cstrong\u003eDNV-RP-B401\u003c\/strong\u003e for ships. Whatever the calculation says,\n\u003cstrong\u003ereplace at about 50% wasted\u003c\/strong\u003e — output falls away as surface area\nis lost.\u003c\/p\u003e\n\u003cp\u003eWrong alloy for your water? See\n\u003ca href=\"\/collections\/saltwater-anodes\"\u003esaltwater anodes\u003c\/a\u003e — zinc to ASTM B418\nType I and aluminium.\u003c\/p\u003e","brand":"Dibblee","offers":[{"title":"318 x 65 x 32 mm — 0.7 kg","offer_id":50199409754389,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"457 x 102 x 64 mm — 3.5 kg","offer_id":50199409787157,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"229 x 229 x 25 mm disc — 2.25 kg","offer_id":50199409819925,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true},{"title":"140 mm dia button — 5-1\/2 in","offer_id":50199409852693,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}]},{"product_id":"magnesium-hanging-anode","title":"Magnesium Hanging Anode — Freshwater Berth","description":"\u003ch2\u003eMagnesium Hanging Anode — Freshwater Berth\u003c\/h2\u003e\n\u003cp\u003eA suspended magnesium anode on a cable, dropped over the side and bonded to the vessel. For boats lying in a freshwater berth, and for laid-up vessels where the hull anodes are out of the water or already spent.\u003c\/p\u003e\n\n\u003ch3\u003eWhy magnesium in fresh water\u003c\/h3\u003e\n\u003cp\u003eFresh water is far more resistive than sea water, and zinc cannot drive enough\ncurrent through it — it polarises, skins over and stops protecting while still\nlooking perfectly serviceable on the hull. \u003cstrong\u003eMagnesium is the fresh-water\nalloy.\u003c\/strong\u003e If your vessel works the Great Lakes, the St Lawrence, or any\ninland waterway, zinc is the wrong metal no matter what the chandlery stocks.\u003c\/p\u003e\n\n\u003ch3\u003eSizes and weights\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eSize\u003c\/th\u003e\n\u003cth\u003eWeight\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSuspended anode with 4 m cable — 1.0 kg\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.0 kg (2.20 lb)\u003c\/td\u003e\n\u003ctd\u003efor berthed or laid-up vessels\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cem\u003eDimensions in millimetres with inches alongside. Weights are nominal and\nconfirmed at quotation.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eAlloy — ASTM B843\u003c\/h3\u003e\n\u003cp\u003eMagnesium anodes are cast to \u003cstrong\u003eASTM B843\u003c\/strong\u003e, which covers two\nalloys, and the choice between them matters more than most people expect:\u003c\/p\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eAlloy\u003c\/th\u003e\n\u003cth\u003eOpen circuit potential\u003c\/th\u003e\n\u003cth\u003eUse\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003eAZ63\u003c\/strong\u003e — standard potential\u003cbr\u003e(Al 5.3–6.7%, Zn 2.5–3.5%, Mn 0.15–0.7%)\u003c\/td\u003e\n        \u003ctd\u003e≈ −1.55 V\u003c\/td\u003e\n        \u003ctd\u003eThe default. Steel and GRP hulls in fresh water, and \u003cstrong\u003ethe right\n        choice near aluminium\u003c\/strong\u003e.\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\n\u003cstrong\u003eM1C\u003c\/strong\u003e — high potential\u003cbr\u003e(Mn 0.5–1.3%, Fe ≤0.03%, Ni ≤0.001%, Cu ≤0.02%)\u003c\/td\u003e\n        \u003ctd\u003e≈ −1.70 to −1.75 V\u003c\/td\u003e\n        \u003ctd\u003eHigh-resistivity water and soil, where the extra driving voltage is\n        needed to push current.\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eA caution on aluminium\u003c\/h3\u003e\n\u003cp\u003eMore driving voltage is not better. \u003cstrong\u003eAluminium suffers alkali attack and\nhydrogen blistering of its paint when driven more negative than about\n−1200 mV\u003c\/strong\u003e, and high-potential magnesium will do exactly that. On aluminium\nhulls, outdrives and sterndrives use the standard-potential alloy and watch the\nprotection potential. Blistering paint and unusually fast anode wastage are the\nsymptoms of over-protection, not of needing more anode.\u003c\/p\u003e\n\n\u003ch3\u003eHow magnesium compares\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003e\u003c\/th\u003e\n\u003cth\u003eZinc\u003c\/th\u003e\n\u003cth\u003eAluminium\u003c\/th\u003e\n\u003cth\u003eMagnesium\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eWater\u003c\/th\u003e\n\u003ctd\u003eSalt\u003c\/td\u003e\n\u003ctd\u003eSalt and brackish\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eFresh only\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eCapacity\u003c\/th\u003e\n\u003ctd\u003e≈ 780 A·h\/kg\u003c\/td\u003e\n\u003ctd\u003e≈ 2000–2500 A·h\/kg\u003c\/td\u003e\n\u003ctd\u003e≈ 1100 A·h\/kg\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eRelative life, same size\u003c\/th\u003e\n\u003ctd\u003e100\u003c\/td\u003e\n\u003ctd\u003e130–150\u003c\/td\u003e\n\u003ctd\u003e≈ 30\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003ctd\u003eASTM B418\u003c\/td\u003e\n\u003ctd\u003eno composition standard — qualified by test\u003c\/td\u003e\n\u003ctd\u003eASTM B843\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eMagnesium drives harder than either of the others but spends itself doing it —\nroughly a third of the life of zinc for the same size. That is the trade, and it\nis why magnesium belongs in fresh water and nowhere else. Put it in salt and it\nwill waste in a season.\u003c\/p\u003e\n\n\u003ch3\u003eSizing and replacement\u003c\/h3\u003e\n\u003cp\u003eSizing comes from \u003cstrong\u003eABYC E-2\u003c\/strong\u003e for boats and\n\u003cstrong\u003eDNV-RP-B401\u003c\/strong\u003e for ships. Whatever the calculation says,\n\u003cstrong\u003ereplace at about 50% wasted\u003c\/strong\u003e — output falls away as surface area\nis lost.\u003c\/p\u003e\n\u003cp\u003eWrong alloy for your water? See\n\u003ca href=\"\/collections\/saltwater-anodes\"\u003esaltwater anodes\u003c\/a\u003e — zinc to ASTM B418\nType I and aluminium.\u003c\/p\u003e","brand":"Dibblee","offers":[{"title":"Suspended anode with 4 m cable — 1.0 kg","offer_id":50199409918229,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}]}],"url":"https:\/\/www.kentershackle.com\/collections\/freshwater-anodes.oembed","provider":"Kenter Shackles","version":"1.0","type":"link"}