Tyre Deflator are the easiest way to deflate your tyre for increased traction. Simply screws onto your tyre valve to automatically deflate all tyres to your preset pressure (from 0.40 bar to 2.0 bar).All you need to do is screw it onto the valve stem and wait until the deflators have done the job. Once you have preset your deflator, you will not need to set them again, unless you wish to change the pressures you are running at. This is achieved without use of a tool: adjustment of the Stauns is in fact very easy and is controlled by an adjustment knob. The lock ring prevents accidental changes in the pressure desired, but permits easy resetting of the pressure. When the tyre reaches its predetermined pressure, the valve shuts off automatically.