The air valve is a replacement for select SaluSpa drop stitch inflatable hot tubs and Hydro Force stand-up paddleboards. The replacement valve is used for inflating and deflating drop stich hot tubs and stand-up paddleboards. The replacement cap covers the valve to lock in air. Just screw the valve into the hot tub liner or stand-up paddleboard body and you’re ready to inflate. Once inflation is complete, close the cap to prevent air leakage.