Features:
Multifunction, time / voltage / temperature display
Power Supply Voltage: DC 7~30V (with anti-reverse protection)
Display: Four 0.30" LED digital tube
Display Color: Red
Refresh rate: about 300ms / times
Measuring temperature: -50'C to 125'C, DS18B20 sensor
Measuring Accuracy: 0.0625 degree
Sensor Cable Length: about 1m
Sensor probe: DS18B20
Some Application: for Measure Car, Room, Water, Refrigerator, Aquarium Temperature And DIY etc.
Measuring voltage Range: 0~30V DC, Accuracy: ±0.02V
Clock: 24-hour, the battery backup is available 2 years

Display modes:
Only display time
Only display the voltage
Only display temperature
Time temperature voltage alternating display

Time setting button:
Short press to adjust the hours, minutes (flashing), short press again to exit
Short press the "Mode setting button", the clock starts running
Wiring of voltage measure:
Red: Power Supply +
Black: Power Supply -, Measure Voltage -
Green: Measure Voltage +