Pentek PCC212 Phosphate Filter Cartridge, 9-3/4" x 2-5/8" Inhibits scale and rust buildup in residential and commercial applications Prevents staining caused by precipitating iron Food-grade hexametaphosphate media Initial pressure drop of 1 psi at a flow rate of 1.5 gpm Temperature range of 40 to 100 degrees F (4.4 to 37.8 degrees C)