There is another sleeper back light on Ebay too. This baby takes 3 aaa batteries, and my wife claims it is just as bright or brighter then the Superflash. Plus, it has/uses the same mount as the Superflash. Guess what, this rear light goes for $2.99 free shipping and best offer. Being the cheapy that I am, I offer $2.50. I am at work and Ebay is barred, when I get home, I will post a link.