The device is excellent: both quality and functions. This is the smart active balancer NEEY 4Th version with 4Amps active balance current and it's fully configurable via its bluetooth connecting app for Android and for iPhone. Configurable (and all working as intended): voltage difference to start balancing; starting voltage to start balancing, lower voltage to stop balancing. All as should be and it works fine. The most exceptional feature of particular this balancers is that it transfers full 4Amperes current (or whatever you set in settings, can set lower balancing current) between highest and lowest voltage cells until they equal then goes to the next highest difference pair and so on; contrary to other active balancers which are described as "maximum balancing current 5A" for example but their balancing current depends on voltage difference: for lower voltage differences between cells they transferring only low current, full 5A will be only when difference is very big.

good