This single unit comes pre-wired and pre-plumbed for your convenience. The compressor is mounted to the tank using heavy duty vibration isolators to help ensure quiet operation and the tank recharges from 110 to 145 PSI in just over a minute! With such robust yet compact performance the HornBlasters 228H has proven itself perfect for mobile pneumatic applications such as powering air horns, inflating tires, or even using air tools. The unit comes with a pressure switch, safety blow-off valve, drain cock, and a 1/4" compression fitting. All you need to do is supply power and the unit automatically builds up to 145 PSI and turns off. When you drop below 110 PSI the compressor will kit back on and recharge your air supply. All tank fittings are installed, and the compressor is ready to be fired up!