The Culligan® RFC-BBSA Level 4 Premium Filtration cartridge reduces sediment, rust, scale, dirt, coarse sand, sand, fine sand, silt, bad taste & odor and chlorine taste & odor. The replacement cartridge fits the HD-950A. The filter is recommended for use with city and well water supplies. The cartridge life is up to 3 months or 5,000 gallons. Cartridge change reminder sticker included.