Anti-Corrosion Washers

The NOCO Anti-Corrosion Washers (model B603) are engineered fastening components designed to protect critical hardware in saltwater and freshwater marine environments. After decades on the water, any experienced boater knows that standard steel fasteners corrode at an accelerating rate once exposed to moisture, salt spray, and electrolytic action. These washers serve as a sacrificial and protective barrier, preventing galvanic corrosion that can seize bolts, create dangerous structural weaknesses, and compromise the integrity of your vessel's systems—from through-hulls to engine mounts to electrical connections.

NOCO's anti-corrosion washers are manufactured from corrosion-resistant materials formulated to isolate fasteners from direct contact with conductive saltwater and metal surfaces that accelerate oxidation. The washers' design distributes load evenly while their chemical composition resists rust formation and electrolytic degradation far longer than bare steel. Installation is straightforward—place the washer between the fastener head and the mounting surface—and the compact 3.75 x 3.7 x 3.9-inch package contains a sufficient quantity for multiple applications aboard most vessels. Their lightweight construction (0.48 lbs) ensures minimal weight penalty while delivering maximum protection against the relentless marine environment.

Marine mechanics, boat builders, and serious DIY boaters benefit most from keeping NOCO Anti-Corrosion Washers in their toolbox for routine maintenance, repairs, and hardware replacement. Whether you're reinstalling cleats, securing battery terminals, fastening sea cocks, or refurbishing through-hull fittings, these washers extend the serviceable life of your fasteners by years. They pair effectively with stainless steel and galvanized bolts, creating a multi-layer defense against corrosion that keeps your rig operating reliably and safely through saltwater seasons and extended freshwater deployments.