Air Vacuum Pump. Air operated, automatically shut down when the receiving container is full. Features 1/4" NPT air connection, 1" suction inlet, no moving parts and no moving parts. Includes 2" NPT bung adapter, suction hose, and air connection kit. Applications: cleaning pits at service stations (waste oil, gravel, cigarette butts, bolts, etc.). Cleaning bilges, emptying engine and gear oil at marinas. Cleaning machinery for metalworking (cooling liquids with metal parts). Cleaning dry dust from conveyor belts. Can be used with most any fluids and solid particles up to 3/4 inch. Working pressure of 60 PSI. (4 bar).