Red LED voltmeter

Model: AB801-RD.
Red LED voltmeter.
This is a mini DC voltmeter with LED display. Thanks to the small dimension it can be easily integrated into your project. It has three wires (yellow, red and black) and can measure up to 100 V.
Specification:
Power Supply: 3.5 ~ 30 V.
Measured Voltage: 0 ~ 100 V (3-wire mode) or 0 ~ 30 V (2-wire mode).
Working Temperature: -10～+65℃.
Measure Speed: 200 ms a time.
Accuracy: 3%.
Color: red.
Usage guide:
This voltmeter has three wires, and they are:
Yellow: anode of measured voltage.
Red: anode of power supply for the voltmeter.
Black: common cathode of measured voltage and power supply.