Features: 1,The first time the product is powered on, the default is ternary lithium battery 3 strings of voltage 2,In the normal display state, if there is no operation button for 10 seconds, the product automatically turn off the display and enter low power consumption. You can also manually short the button to turn off the display and enter low power consumption; when the product is in the off state, short the button to turn on and display the power. 3,In the setting state, if the button is not operated within 5 seconds, it automatically return to the normal display battery. 4,After setting, and hold the button for 2 seconds to save the data and return to the display battery status (or wait for 5 seconds to automatically return) 5,Short the button to set the number of strings or voltage of the battery; for details, please refer to the above table for option settings. Specification: Working current: Less than 10mA Display mode: LED indicator Refresh rate: 500ms/time Appearance size: 46mm x 15mm x 3mm Item model number: 4615 Product working voltage: DC5V-30V Notice: 1,Please do not exceed the operating voltage. Exceeding the operating voltage damage the product. 2,The product has two versions of high and low voltage, please select the electricity meter within the voltage range. 3,Please do not use this product outdoors, this product is not waterproof Material: Plastic colour: black Package Contents: 2 x Battery indicator board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.