For straight launches on asphalt, sand, and dirt a rear locker is not enough. You need equal rear tire pressures. For perfect pressure equalization use our DIG-8255. It features a 0-60 PSI digital gauge for accurate and easy-to-read pressures, top quality clip-on closed European chucks, braided air line, billet alum. grip body, and micro adjust valve along with a side pressure release button to decrease tire pressures. Laser etched Power Tank logo. 1/4" industrial inlet plug plugs right into most hoses.