Omnifilter, Quick Change Replacement Water Filter Cartridge, For The US1750 Undersink Water Filtration System, 0.5 Micron Rating For The Reduction Of Sediment & Rust Particles, Chlorine Taste & Odor, Cryptosporidium & Giardia Cysts, & Lead & Mercury, Provides Healthy, Great Tasting Water For Your Home & Is Easy To Install/Replace With No Mess, Capacity Of 6 Months.