GEREE DC 12V Car Battery Against Excessive Discharge Controller Sound and Light Alarm/Anti-Over-Discharge Protection Board It suitable for 12V battery, when the battery voltage is normal, the green light is on board, the output ON; when the battery is over-discharge (less than 10.4V or so), the board will automatically disconnect the battery output, the red light is on and the buzzer is called, to achieve sound and light alarm, enabling master battery discharge status, prevent over-discharge the battery, damage the battery. The main chip: LM358. The board after the maximum allowable current 30A, suitable for most 12V battery. The input and output are used pluggable terminal blocks for ease of use. GEREE 12V Car Battery warranty--30-Day Money Back Guarantee -- 12 Month Replacement Warranty -- Lifetime Support Guarantee