QNBBM balancers are designed to actively transfer energy from the highest charged cell over to the lowest charged cell. A voltage difference of 1V will draw a current of 3A, a 300mV difference will draw 1A. Using these balancers in a high capacity bank with slight capacity differences helps get more usable capacity out of the bank before the lowest capacity cell nears empty by transferring energy into it from other higher charged cells. LED lights on top indicate whether the balancers are in balance with each other, are charging other modules, or are receiving a charge.

There are two types for sale, 12V and 3V.
Voltage range per type:
12V: 9V-15V
3V: 2V-5V