Specification: and Measuring range: DC 0V- 30V Optional Display Color: Blue/Green/Red Display: three 0.56 "digital tube Measurement accuracy: 1% Refresh rate: about 300mS / times Input impedance: > 100K Operation Temp: -10-and65 Size: approx. 4.7 x 2.8 x 2.2cm (1.85'' x 1.10'' x 0.87'') Cable length: approx. 20cm 3 colors have different working current and Input range Input range: DC4.50-30.0V( red)/DC4.70-30.0V(green)/DC5.00-30.0V(blue) (Max Input: DC 30V. The device can be damaged if input is over 30V) Working Current: red< 23mA,green< 18mA,blue< 13mA Wiring: Red: power supply and. Black: power supply -, measure -. White: measure and. Package included:1 x digital voltmeter Note: Please allow 1-5mm errors due to manual measurement Item color displayed in photos may be showing slightly different on your computer monitor since monitors are not calibrated same. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.