NOTE: Not recommended to be compatible with low strings, The indicator light will flash and report an error. Before connecting the equalization board, be sure to check whether each battery is wired correctly, and do a good job of insulation. otherwise it will short-circuit and burn the board. If Buyer short-circuits and burns the board, Buyer needs to bear the responsibility instead of returning it. Thank you for acting with conscience. Applicable battery type: NCM(Li-ion)/LFP, NOT support LTO; Single voltage working range: 2.0V-4.5V; Static working current: 0.01mA; Suggested battery capacity: below 30AH, If more than 30AH, pls choice high efficiency flying capacitance equalization, search "B09MS8Z58H" to purchase. Balance method: Detect that the voltage difference between adjacent batteries is greater than 0.1V to trigger the start of equalization, and the adjacent battery voltage difference is less than 0.03V to stop working, the board enters under-voltage protection dormant state. Voltage balance accuracy: 30mV (typical value) between adjacent voltages; Balance current: 0.1V voltage difference 0.5A-0.7A balance current, the maximum balance current is 1.2A when the voltage difference is above 0.2V. The smaller the voltage difference between adjacent batteries, the smaller the equalizing current. Balance indication: 1) When the equalization light is on, the equalization work is turned on; 2)The equalization light goes out, the equalization circuit sleeps; 3)The equalization light flashes, it drop cells, or the circuit is faulty. Note: If the battery is connected, it must be used with the BMS protection board. The charge/discharge voltage difference triggers the balance board to work to achieve energy transfer balance. Applicable battery: NCM(Li-ion)/LFP, NOT support LTO. Single battery voltage: 2.0-4.5V Suggested battery capacity: below 30AH Voltage balance accuracy: 30mV (typical value) between adjacent voltages Balance method: Detect that the voltage difference between adjacent batteries is greater than 0.1V to trigger the start of equalization, and the adjacent battery voltage difference is less than 0.03V to stop working. Balance current: 0.1V voltage difference 0.5A balance current, the maximum balance current is 1.2A when the voltage difference is above 0.2V. Under-voltage protection dormant voltage: The adjacent voltage difference is less than 0.03V and enters dormant state. Static working current: 0.01mA Accessories: 0.98ft 22awg terminal wire Product Size: (4S) L55*W23*T6.5mm/2.16x0.90x0.25inch Balance indication: 1) When the equalization light is on, the equalization work is turned on; 2)The equalization light goes out, the equalization circuit sleeps; 3)The equalization light flashes, it drop cells, or the circuit is faulty. Wiring definition: Note: The cable plug needs to be inserted obliquely, first touch the "B-" pin and insert it obliquely, otherwise it may cause the board to burn out! B-: the total negative pole of the battery pack (the negative pole of the first battery) B1: The positive pole of the first battery B2: The positive pole of the second battery B3: The positive pole of the third battery B4: The positive electrode of the 4th battery Package Included: 1x Active Balance PCB with 5pin Cable.