Measuring range: DC 2.5~30V Two-wire  
Measurement accuracy: 0.1V 
Display: Three 0.28 " LED digital tube 
Display Color: Red, Blue, Green or yellow
Refresh Rate: about 500mS/times 
Operating Temperature:-10°c ~ +65 °c 
Current consumption: generally 5-15mA, less than 20mA 
Reversal protection: Yes
Cutting size: 23.5mm x 10mm 
Mounting holes distance: 29mm 
Power supply same source, self-Power

Wiring: 
Red: Power Supply +, Measure Voltage +, (2.5~ 30V DC) 
Black: Power Supply -, Measure Voltage -