The Pentair Pentek WPX100BB97P is a 100 micron polypropylene string-wound sediment cartridge built for 10-inch Big Blue whole-house housings. A durable polypropylene string is wound in a precise pattern around a rigid polypropylene core, reducing coarse sediment such as dirt, sand, silt, rust and scale particles. Its 100 micron rating makes it an ideal high-flow first stage that captures larger debris and helps protect finer downstream filters. Polypropylene will not impart taste, odor or color and is chemical-resistant, so it works well on both municipal and well water and with many industrial fluids. The WPX-BB media is a fibrillated polypropylene fiber cord wound for greater surface area and high dirt-holding capacity, with an initial pressure drop of under 8 psi at 40 gpm and a temperature rating of 40 to 165 degrees F. Unlike the WP-BB media, the WPX-BB cartridge is manufactured without any static-reducing agent, making it the preferred choice when start-up foaming is a concern. This cartridge measures 4.5 inch in diameter and 9-7/8 inch long and fits standard 10-inch Big Blue housings that accept 4.5 inch diameter cartridges. For best results, replace the cartridge when you notice a drop in water pressure or water quality, generally every 3 to 6 months depending on incoming water quality. This is a sediment cartridge only and is not a purifier; do not rely on it to make microbiologically unsafe water or water of unknown quality safe to drink.