Water filter cartridges undersink - fine filtration carbon impregnated cellulose pack of 2 Universal slim design installs quickly and easily to replace cartridge of Culligan undersink filter Nos.US-550 and US-600. Also fits Culligan Nos.US-560, US-560K, CTR-210, RO-3167, SY-2000, and SY-5167; Omni, Sears, Fulflo, Teledyne Water Pik, Ace, Flotec, Honeywell, General Electric, American Plumber, and most other standard size water filters. Activated carbon impregnated cellulose provides clean, fresh drinking and cooking water by reducing sediment, chlorine taste/odor, unpleasant tastes and odors (5 nominal micron rating). Up to 3-month/250-gallon life. NSF International tested and certified.