The self contained Poly-Hand Pump works independently of air pressure. Requires no adapters and delivers by positive pressure on the down stroke of the piston. The pump will deliver against a 3.65-meter (12 ft.) head of water and empty a drum or carboy to within 3mm (1/8") of the bottom. Made entirely of polyethylene, it is inert to strong acids, alkalies and many solvents. All pumps individually packed.