it is a 6 volt head light which is what the white wire that comes off your motorized bicycle is. as i said it is awesome. you need to start the bike with the light of and then i turn it on. i think it reduces your spark a little so the bicycle engine doesn't fire up real easy with it on. however once running i turn it on and loose no performance or anything thing else i just get a nicely lighted road in front of me for driving at night. the road i take home from work has no street lights at all and no problem with norman light. i even had the light give me heads up on a deer that was crossing because it lit up his eyes. i have a 70cc bicycle motor