Galvanic Corrosion can destroy your engine! Stop it today with our replacement Aluminum plug. Easy to install. Simply replace your existing 18mm - 1.5 steel plug. Anodized Gold For strength and looks! One washer is included. The Gold Standard in Engine Protection! Accept NO substitutions. We bring superior engine protection to you! Suzuki Outboard 6061 Aluminum Exhaust Port Plug. Replaces your stock steel plug and prevent galvanic corrosion. This corrosion has been known to destroy the housing and the only repair is expensive welding. Solve it NOW! Easy to install, just remove the original an replace with our aluminum plug.