Smittybilt's Rapid Air Deflator (RAD) operates by threading on to your valve stem and then removing the valve core from the stem and capturing it inside the brass housing. This makes it incredibly fast, and you never have to worry about losing the valve core. This tool will give you the precise air pressure you need utilizing a calibrated dial with one psi increments. With an easy to read 0-60 psi 2-inch diameter gauge, Smittybilt's RAD takes the guesswork out of airing down.