I do agree the adapter is simpler but it makes no sense to spend $30USD on something I can achieve in ten minutes on my shop bench. The issue is with the voltage. The polarity was confirmed correct with my multimeter and the fact that the wire colors match and the flashlight and socket only go together one way, avoiding the wrong polarity. The voltage is with the car on because it will be plugged in with the car running. I've been away and I haven't been ale to check the voltage at the cigarette lighter.