I'm afraid I got taken on this item found on ebay. It's a lipo voltage checker where you just plug in your balance connector and the cellmeter is supposed to read the voltage of each cell, then the total of all cells. Also you can set it to give a low voltage warning and mount it in your plane. This one shows nothing at all and when I push the Preset button it sounds a loud beep and the red light comes on. If you have one of these and it works maybe you can give me some info on how to get this thing to work. Otherwise I'm out 10 bucks. It ain't much, it's just the principle of the thing. I can no longer find the seller on ebay.