This product is suitable for at least 2S Working current:<10mA Working voltage: DC5V-30 Display mode: LED indicator Refresh speed: 500ms/time Appearance dimension: 46mm * 15mm * 3mm LED displays different colors for different battery types: Red light=lithium ternary battery Green light=lithium iron phosphate battery Yellow light=lead acid battery Function setting: 1: Press and hold the key for 2 seconds to enter the setting state: the mode light (battery 1 type) flashes, and the string number light is always on; Briefly press the key to select the battery type. 2:After confirming the battery type, press and hold the key for 2 seconds to enter the string number 2/voltage setting (the mode light is always on, and the string number/voltage light flashes) 3. Press the button to set the battery string number or voltage; Please refer to the above table option settings for details. 4:After setting, press and hold the key for 2 seconds to save the data and return to the display of 4 power status (or wait for 5 seconds to automatically return) 5 In the setting state, if there is no operation button within 5 seconds, the power will automatically return to the normal display. 1. The first time the product is powered on, the default is 3S voltage of ternary lithium battery. 2. In the normal display state, if there is no operation key within 10 seconds, the product will automatically shut down, display and enter low power consumption. You can manually press the key briefly to close the display and enter low power consumption; When the product is turned off, press the key briefly to turn it on and display the power.