New Open Box. The Filters Fast FF21200 Replacement Water Filter is designed for use with various brands such as Whirlpool, Maytag, Kitchen Aid, Kenmore, and Thermador. This carbon/charcoal filter has a capacity of 300 gallons and is suitable for household use. With one-stage filtration, this white filter is a convenient and effective way to purify your water for your kitchen needs. B1