The TireMinder Wireless 4 Tire Pressure Monitoring System is designed to continuously monitor your vehicles tire pressure and temperature, offering both a visual and audible blow-out warning. The wireless tire transmitters screw onto the valve stems allowing you to easily monitor up to 22 wheels.  The digital monitor signals and sounds alarms for tire pressure loss or if tire temperature exceeds 167 degrees F.  Includes: Monitor (dimensions 2" x 3-1/4") heavy duty/multi-angle bracket, 4 screw on pressure/temperature transmitters (TMT400C) 12 v car charger, 4 extra lithium batteries, 4 anti-theft locks with screwdriver.