PP-S-1 Harmsco Replacement Filter CartridgeThe Harmsco PP S 1 Absolute Rated Filter Cartridge uses the Poly Pleat technology to substantially reduce cysts, sediment, turbidity, and harmful organisms. Poly Pleat cartridges are ideal for municipal and surface water filtration as they feature a long filter life and exceptionally low initial pressure drop. Independently tested to certify filter performance at an absolute rated 1 micron media that removes cyst sized particles for safer, healthier