Universally suitable for car, bike, basketball and swimming ring needs, this digital inflator pump is handy car accessory. 【Preset Tyre Pressure & Auto Shutoff】: You just need to start the engine, plug the cigarette lighter into the car's 12V power outlet, link the tyres, press the‘Switch button’to select the mode, and then press the‘+’and ‘-’buttons to preset the required pressure.When the Portable tyre inflator reaches the required pressure,the digital air compressor will automatically switch off, so you don't have to worry about over-inflation.