Pentek WP5BB20P #355223 Polypropylene 5 micron String Wound Sediment Water Filter. WP Series 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. WP Series 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 like the CW. These string-wound cartridge styles are capable of withstanding temperatures up to 165ºF (73.9ºC), and will accommodate flow rates between 7 and 10 GPM with minimal pressure drop. WP Series cartridges are suitable for a wide variety of sediment filtration applications, including municipal and well water as well as many industrial fluids. This is a very high quality sediment filter.