Sigh. I mention this everytime tail-light comparisons show up on BF. An www.allelectronics.com Xenon strobe light unit conected to your headlight battery or with its own battery pack can give you rapid, eye-searing flashes for $10-$20. It just does not look like one of the stock bike tail lights but I would rather be Fred then Dead. Since I got a Radio Shack Xenon strobe tail-light nearly 20 years ago no club I go on night rides with will let me be any where but last in the group or pace line.