VSTM Smart Car TPMS Tyre Pressure Monitoring System Solar Power Digital LCD Display Auto Security Alarm Systems Tyre Pressure Features: Real time Monitor tire pressure can improve fuel efficiency, prolong tire life, increase traffic safety and monitor temperature. LCD displays tire pressure andtemperature Visual and sound warning Air leakage warning, low pressure warning, high pressure warning High temperature warning, low power warning and no signal warning Solar power for normal use. Available USB charge for sunless day Monitor x1 Solar Power Charging : up to 15% conversion efficiency Solar Panel : Poly crystalline silicon material Wireless Frequency : 433.92MHz Built-in Battery : 400 mAh / 3.7V LED Display : 2.7 inch Material : ABS + PC Working Temperature : - 20 ~ +80 Charging Socket : Micro USB / DC 5V Weight : 71g External Sensors x4 ( Optional ) Battery ModelCR1632 Working Temperature : - 40 ~ + 120 Working Pressure Range : 0 ~ 4.1 bar / 0 ~ 60 psi Pressure Accuracy : 1.5 psi / 0.1 bar Temperature Accuracy : 3 Wireless F requency : 433.92MHz With Anti-theft Design Material : Nylon Glass Fiber (PA66+30%GF) Engineering Plastic Weight : 11g Size : 23() *18 (H) mm Battery Life : 2 years Internal Sensors x4 ( Optional ) Battery ModelCR2032 Working Temperature : - 40 ~ + 120 Working Pressure Range : 0 ~ 4.1 bar / 0 ~ 60 psi Pressure Accuracy : 1.5 psi / 0.1 bar Temperature Accuracy : 3 Wireless Frequency : 433.92MHz With Anti-theft Design Material : Nylon Glass Fiber (PA66+30%GF) Engineering Plastic Weight : 39g Battery Life : 5 years