Pentair Pentek WP-BB Series Cartridges are manufactured in 10" and 20" lengths and in 4.5" diameters from a durable polypropylene string that is wound around a rigid polypropylene core. The WP-BB Cartridges are an economical solution to reduce fine sediment including rust, sand and scale particles. The material in the WP-BB Cartridges is a fibrous polypropylene media wound in a precise pattern around a polypropylene core, providing greater surface area to maintain high flow rates. The WP-BB Cartridges are manufactured using an -static agent during the winding process to reduce the electrical charges produced during the winding process. These string-wound cartridges are capable of withstanding temperatures up to 165°F (73.9°C), and will accommodate flow rates between 10 and 65 GPM with minimal pressure drop. WP-BB Series Cartridges are suitable for a wide range of sediment applications including municipal and well water, and are chemical so they can be used with many industrial fluids. Note: The -static agent used in the WP-BB Cartridges may cause some foaming during start up of a new cartridge. If foaming