Features： 1、HIGH ACCURACY: Mini digital DC voltmeter possess high accuracy, the refresh rate is about 300mS once 2、0V-30V MEASURING RANGE: Measuring range from 0V-30V, support low start working voltage, the minimum is 4.7V 3、REVERSE CONNECTION PROTECTION: Come with reverse connection protection function, no burning when reverse connection 4、LED DIGITAL TUBE: Using three digit 0.36in LED digital tube, which possess high brightness and clear display 5、FOR DIY PRODUCTION: Made of PCB material, with reliability and miniaturization, good maintenance and interchangeability, used for DIY production Specification： Item Type: Mini Digital DC Voltmeter Material: PCB Purpose: DIY production Measuring Range: 0.00V-30.0V Power Supply Range: DC 4.70-30.0V Maximum Input: DC 30.0V Allowable Error: ±1%; When Greater Than Or Equal To 10V: ±0.3V; When Less Than 10V: ±0.10 Input Impedance: > 100K ohm Working Current: Red <23mA Refresh Speed: About 300mS once Display Mode: Three digit 0.36in LED digital tube Lead Length: Approx. 15cm / 5.9in Installation Hole: Hole Pitch: Approx. 28mm / 1.1in, Hole Diameter: Approx. 2.8mm / 0.11in Working Temperature: -10℃~65℃ Package List： 2 x Mini Digital DC Voltmeter