6) AP420 (5527407/55274-07) Hot Water Protector/Scale Inhibitor Alternative Replacement Water Filter Cartridges by CFS

6) AP420 (5527407 / 55274-07) Hot Water Protector / Scale Inhibitor Alternative Replacement Water Filter Compatible Cartridges by CFS This cartridge has the 2.5" x 9.75" universal dimension that is compatible with a wide array of water filter housings such as Whirlpool, GE, 3M Aqua Pure, Pentek, American Plumber, etc... Siliphos is the amazing ingredient which allows this cartridge to protect your hot water heater from the deleterious effects of corrosion and hardness. It sequesters the hardness ions thus inhibiting them from precipitating out of the water to create scale. Scale can decrease your hot water efficiency by 30 - 40%. Also the siliphos reacts with the hardness carbonate to secrete a thin glass-like coating on the interior metal surfaces thus protecting from corrosion. Will trap dirt / sediment down to 5 microns. This is a non OEM replacement product.