Works exactly as described.
I have a dash cam plugged into the cigar lighter in my Ford Fusion. The lighter is "hot" for up to an hour after shutting the car off, so my dash cam kept running long after it was needed, filling up the memory card with nothing as well as draining the car battery. I put the cut off switch controller between the cigar lighter and the dash cam and now the dash cam shuts off less than a minute after I turn off the car. Exactly what I wanted to happen! Came with no user guide, instruction manual or data sheet, however. If you don't know what you're doing, then you might want to consider professional assistance installing it.
Verified purchase: YesCondition: New