I bought one and located a broken wire in like 2 minutes that ran the length of the vehicle in a harness. It works better than the Power Probe ECT3000.
From what I have seen on RU-vid it does not need to be hooked up to the battery like in the video (unit has internal battery) I'm not sure why it's hooked up here. I think reason it has two output wires on unit is to check continuity of a circuit... I think. I want to get one to find out, looks handy