inflation/deflation
The volume of air displaced with each pump stroke is 2.6 L.
To inflate, connect the hose to the "Inflate" side of the pump.
To deflate, remove the valve from the vale holder in the bladder. Connect the hose to the 'Deflate side of the pump. And hold inside the opening of the bladder, while pumping.
Bend your knees to make it more comfortable when pumping.