The Boston valve is a 2-way screw valve that keeps air in the chamber. A check cap prevents air from escaping as soon as the pump hose is removed. To deflate, simply open the entire valve; to inflate, only the closure cap needs to be opened. Inflating and deflating is very easy and quick, as the airflow is always under control. It features a multifunctional carrying handle and/or paddle holder to relax your hands. The Sevylor Seatography helps you align your seat optimally to find the most comfortable position. The new free-floating Sevy-Suspension seat attachment creates shallower seat depressions at the bottom, making it easier for you to paddle and achieve the optimal seating position. Extremely robust and durable Sevy-Strong tarpaulin with a large surface area to prevent potential air loss.