DROK 0.56" Fahrenheit Scale Car Digital Temp Clock Volt Meter 3in1 Yellow LED Auto Gauge Thermometer With 18B20 Probe Time/voltage/temperature 3 in 1 digital meter of four operating modes Waterproof DC18B20 sensor probe measuring -67F to 257F and with high accuracy of about 0.2 c 12-hour time meter with power-off memory function and its battery is available for 3 to 4 years Adopts SMD technique; its digit would not shake; 4-digit LED display Has reversed-connection protection, meaning the meter will not burn when being connected reversely