The safety valve is a "push-in" valve used in a safety chamber, the separate inflatable area of the ski tube that remains full of air and floats if the main boat tube gets punctured and loses air. The safety valve is much like a valve for an inflatable toy that can be blown up by mouth, though it's simplest to inflate a tube that has a safety valve by using a hand or electric air pump with the proper cone-shaped adapter.
Speed Valve (Raised and Recessed)
A water tube with a speed valve can be inflated with a basic electric air pump, but can also be inflated with a Shop-Vac, a leaf blower, or a vacuum cleaner, as long as the appliance has a reversible-flow switch.
The recessed multi-valve is much like the speed valve, only it has a built-in adapter for air compressors that have a tire fitting.
Always begin by inflating your ski tube's safety chamber. As mentioned above, a safety valve (a low-volume valve) can be found in the safety chamber. Your ski tube is sufficiently inflated when the inner tube is firm and its nylon cover fits tightly around it, free of wrinkles. Avoid over-inflation of the inner tube, which can damage the PVC material and lead to tears in the cover. Note: the main chamber of a towable ski tube cannot be inflated by mouth.
Proper inflation is necessary for safety and for prolonging the life of your ski tubes. Be sure to check inflation levels before each use.