. Features: It runs on a general lead-acid battery and has a powerful battery level testing system. 12/24/36/48/60/72V automatic recognition, practical to use. Recognizes a false battery charging signal. Battery level indicator only, other accessories demo in the picture are not included! Built-in Wiring Method:1. Insert the mating 15cm wire into the reserved terminal position on the back of the product, pay attention to the direction of the plug;2. The red wire is connected to the positive electrode of the battery, and the black wire is connected to the negative electrode. Make sure the wires are in good ;3. Once connected, the product will display the battery count, power percentage, and voltage cycle display. Definition of shortcut keys:1. Short press the U/D button to turn off the backlight, then press the U/D button to turn it off completely and cycle through it;2. Short press the SET button to display the voltage, then short press the SET button to display the percentage and cycle through the display. Specification:Item Name: Battery Level IndicatorMaterial: PlasticDisplay: LED DisplayCase Material: ABSuth Voltage: 9-90VTrouge Temperature: -10°c - 65°cOperating Humidity: 10-80%RHWuth Item Size: 46x25mm/2.52x0.98inPackage Size: 6.5x5x5.7cm/2.56x1.97x2.24inColor: BlackQuantity: 1pcNote: 1. Please allow 1-3cm error due to manual measurement. Pls make sure you do not mind before bidding.2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Included:1pc x Battery Capacity Tester1pc x Power Cable2pcs x Screw