External Sensor:Easy to install, convenient to replaceBattery: built-in CR1632 button cell（Does not contain）Working voltage: 2.0 - 3.6VWorking environment: -30 ~105 Deg.CPressure accuracy: plus or minus 0.1barWaterproof grade: IP67Transmission frequency: 433.92MHzMonitor:Battery type: 280mAh Li-ion battery Working voltage: 2.6-3.6VWorking environment: -20 ~70 Deg.CTransmission frequency: 433.92MHzPressure unit: psi / barTemperature unit: Deg.C / Deg.FFeatures:Type: Intelligent Solar TPMS Car Tire PressureSolar power charging, don’t need to charge by connecting car cigarette lighterColorful LCD Digital displaying, clear to show tire informationRear-time monitoring pressure & temperature of 4 tiresLow air pressure/high temperature alarmHigh Temperature / Leakage / Low Battery AlarmIntelligent Shock Boot when car moving, don’t need to turn on/offWireless connect by sensors, easy installTwo units (PSI / Bar) changeable, you can set the one you like. Package Included:1 set Car Tyre Pressure Monitoring SystemNote:There may be slight size deviations due to manual measurement, different measuring methods and tools.The picture may not reflect the actual color of the item because of different photographing light, angle and display monitor.