The Culligan CW-F 2-pack Fine Filtration cartridge reduces sediment, rust, scale, dirt, coarse sand, fine sand, and silt. The replacement cartridge is designed for use in the following Culligan model filter housings: HF-150A, HF-160, HF-360A, WH-S200-C and most other brands standard size housings. The filter is recommended for use with city and well water supplies. The cartridge life is up to 3 months or 12,000 gallons.