Water filter cartridges whole house sediment pleated paper – medium filtration”omnifilter” Use inside Nos.U25, OB-1 or OB-5 filter housings to extend life of major appliances or provide clean, fresh drinking water by removing sand, silt, rust and loose scale (20 nominal micron rating). Pleated resin impregnated cellulose construction for increa sed efficiency. 5 GPM, 3-month/15,000-gallon life depending on usage and water conditions.