USB or Solar Charging Car TPMS Tire Preure Monitoring System HD Digital LCD Display Auto Alarm tool Wirele 4 external Sensor Notice: Please push left button over 3 minitus to turn on monitor, if it does not work, please try again after charging. Parameter 1.Monitoring system body Operating voltage: 3.7-5V Storage temperature:-30C-90C working temperature:-30C-85C RF Emiion frequency:433.92MH50KHz RF Signal sensitivity:-90dbm Display mode:LCD Color Bright screen current:6mA Black screen current:4mA Size:85*95MM Built-in SensorWorking Temperature:--40 C -125CWorking Frequency:433.92MHZworking humidity:Max95%Tire monitoring range value:0bar-3.5bar Deviation0.013Battery life:5 yearsTransmit power:R&D environment test below-17db Features: Solar power charging; High and low preure, leak alarm; LCD display screen, Simple user interface High accuracy, Using Freescale imported chips; Real-time monitoring tire preure and temperature; Smart start: parking automatically sleep, the car starts automatically wake up. Two units(PSI / Bar) changeable, you can set the one you like. Sensors' batteryChangeable Description: Solve the sensor does not work:Match sensor(Vent)