I have an assemblage which has a light component to it that has not worked for some time. So I decided to rewire the battery pack to an ac adapter and skip the batteries all together. Ah hem, I was a little nervous because apparently the Chinese don't color code wires on small items. So the first thing I had to do was figure out which wire was the positive wire and which was negative. I didn't really want to wire to the adapter wrong, so after some thought I decided to use another battery pack and touch the bare wires to the terminals and see if the lights came on. Well the first try didn't yield any positive results, the wires got hot immediately and the lights flashed off on the battery pack. After switching the wires my assemblage lit right up. So I connected the wires, wrapped the bare ends and plugged it in and it works great!