This light runs off an included replaceable lithim battery. It has a tiny little slide switch in the removeable base to control the LED bulb.
LED Lamp. No transformer required. Turn on and off with small switch on Base that contains a CR927 3V battery. Base is magnetized for hanging. The non-replaceable LED bulb will burn for at least 4000 hours. Base unscrews to replace battery with #2300 Four 3V CR927 batteries.