4.5" x 10" Melt-Blown Filter Cartridge for Big Water Filtration Housing 5MICThis PurePro 4. 5" diameter x 10" long replacement filter cartridge is designed to fit the Big 10" water filtration housing. Reduces fine sediment, including rust, sand and scale particulates as small as 5 microns in the water supply. The melt blown polypropylene construction have graded density layers. The more porous outer layers catch larger particles, while the finer inner layers catch smaller particles. Suitable for use in drinking water