The Inlet Filter is designed to prevent air-borne debris from entering the vacuum pump. It may use stainless steel screen, pleated paper element, or pleated fabric element. The element should be checked daily, and be cleaned if needed. Many pump manufacturers, including Masport, National Vacuum Equipment, Fruitland, Gardner-Denver Wittig, Jurop, Conde and Moro, include an Inlet Filter as an integral part of certain assembled pumps. Add-On Inlet Filters are made by Masport, National Vacuum Equipment and Chandler Equipment.