The 42-inch Eastman Flexible Magnesium Anode Rod helps prolong the life of your water heater tank by attracting corrosion to itself. The rod corrodes through electrolysis, a process that protects the steel walls of the water heater by attracting corrosion to a more noble metal. The anode rod is built with a carbon steel cable and 4 sections of magnesium links. It features a durable stainless steel 3/4 inch x 5 inch NPT nipple connection. Easy to install by attaching it to the top of the tank to keep it steady. The anode rod should be inspected every 2 years and replaced as needed.