Siphon liquids from higher to lower levels effortlessly.  Simply pump the bellows a few times to prime the pump.  Then open the screw top to stop liquid flow.  An internal flapper valve prevents reverse flow. Model 128830 fit 15, 30 and 55 gallon drums with 2" IPS openings.  Ideal for use with water-based fluids, mild corrosives, detergents and petroleum-based fluids.  Pail pump features a convenient bulb-operated siphon equipped with 1-1/16" O.D. unthreaded male bung fitting and siphon hose. Made of polyethylene. Model 128831 is designed for 5 gallon pails