This HDPE Siphon pump is designed for 2" (63 mm) Buttress openings in plastic drums. These siphon pumps are ideal for mildly corrosive liquids up to 140° F, water-based liquids, detergents, even some petroleum products and very simple to operate. Just pump the bellows to start the flow. 5 GPM flow rate with 44" hose Control siphon action by adjusting the air vent at the top of the pump handle. Note: Bellows, hoses, adapters and intake tubes are made of HDPE (High Density Polyethylene)