This is a Red LED Current Meter capable of measuring and displaying current in a circuit up to 10A. It measures 0-9.99A with 2% accuracy. Just apply four wires to your circuit and it will give you a current reading straight away. Easy to use and a good companion to any robot project. Please carefully follow the instructions for wiring. The power supply terminal and measurement terminal of this LED Current Meter use a common-ground connection. So, the measurement must be cascaded after loads. It\’s better to isolate the power supply. Specification Measure Current: 0-9.99A DC Power supply voltage: 4-30V DC Display mode: 3-bit 0.56 Led digital tube Accuracy:2% Opening dimension: 45.5mm*26.5mm Dimension: 48mm*29mm*21mm Shipping List 1x LED Current Meter 10A (Red)