Tuck your feet into our bean bag and get them super comfy, then close the valve and you have your footprint proudly placed in our Happy Feet Footbag. Then pump the bulb which inflates the adjustment bladder and you will tighten up bag until you have the right amount of pressure to give you the control you like. Get to the bottom of the rapid, or pull into an eddy and hit the release valve, now you have excess room again and can lift your knees out easily to relax. This is how we like to define comfort and adjustability that's the Happy Feet Footbag. It comes standard in all Elite Models and comes in Small, Large and Extra Large. The smaller the person the bigger the bag