This double action pump inflates and deflates tubes, airbeds, boats, toys and other inflatables. It delivers a continuous stream of air on both the up and down strokes. Simply turn the release valve counter-clockwise and you're pumping air only on the down-stroke. This is a great option when your inflatable is almost full and there's back pressure. Four universal valve fittings are included. The accordion-style hose stretches to 5 ft. long and interlocks to the pump, so that it doesn't fall off while you're pumping. Capacity is approximately 68 gallons / 60 strokes. Especially great for topping off towables, since peak pressure is 14 psi.