Loctite Tite Foam White Polyurethane Big Gaps Foam Sealant 12 oz. for Indoor & Outdoor Use (Pack of 12)The 29 inch aluminum anode rod from Reliance protects your water heater tanks from corrosion and extends the tank life. The aluminum anode rod is designed to attract the sediments and corrosive elements in the water to keep the tank clean. You can install this in electric and gas water heaters, and the aluminum rod can be cut to fit shorter water heater tanks. Replace each rod once a year in your gas electric water heaters for continuous protection!