Tire Pressure Monitoring System Wireless Solar TPMS, Tire Pressure Monitor Installed on Windowshield with 4 External Sensors Real-time Display Temperature Pressure 22-87 PSI for Car RV SUV MPV SedanUsing TPMS, when the tire condition is dangerous, the driver can immediately receive an audio visual alert,real time monitoring of tire conditionsextend the tire life and ensure safe driving. (It is not recommended to install it on a trailer, as it may work abnormally. For trailers, please choose a device that supports a longer working distance, such as other devices with external antennas.) Specification: Receiver Voltage: 5V Receiver Working