The Culligan P1 2-pack Fine filtration cartridge reduces sediment, rust, scale, dirt, coarse sand, sand fine sand, extra fine sand and silt. The replacement cartridge fits the following models: HF-150 more→A, HF-160, HF-360 and most standard size housings. The filter is recommended for use with city and well water supplies. The cartridge life is up to 2 months or 8,000 gallons.