I'm in the process of modding my U2. I removed the selector ring and out popped the magnet. It's pretty powerful for a little dot of a thing. My U2 cycles back to the lowest level in between levels 1 thru 4. Mkes me wonder how powerful the magnet has to be so that the light level selections transition smoothly. If I stick the magnet on my fridge, I have to slide it off. I have difficulty lifting it. It's that powerful.