Nominal 1 micron WP1BB97P Polypropylene String-Wound Water Filter Cartridges, The US Filter/Ametek/Pentek WP1BB97P water filter string-wound design reduces fine sediment from a variety of fluids, US Filter/Ametek/Pentek WP1BB97P water filter cartridges are wound in a precise pattern around the core providing greater surface area, The result is higher dirt-loading capacity and greater efficiency than standard wound cartridges, US Filter/Ametek/Pentek WP1BB97P sediment filter cartridges are manufactured from a durable polypropylene cord that is wound around a rigid polypropylene core, They are an economical solution to reduce fine sediment, including sand, silt, rust and scale particles, Dimensions: 10"" L x 4-1/2"" W, Micron Rating (Nominal): 1, Temperature Rating: 40F to 165F (4, 4C to 74C), Filter Media: Polypropylene Fiber Cord, Core: Polypropylene, Maximum Flow Rate: 15 GPM (57 LPM); Pressure Drop 4 psi, SKU: CWD2354