The Tyre pressure monitoring system allows you to monitor your temperature and pressure of 4 Tyres on your entertainment system. The device is made up of four Tyre valve replacements which send a RF (Radio frequency) transmission to your headunit. The warnings include slow leak detection, fast leak detection, low pressure warning, high pressure warning and will tell you which tyre has been compromised. The system also allows you to set the pressure and temperature and which you wish to be warned which is great for 4×4 vehicle.