Planet Bike Superflash Stealth (red blinkie light for cyclists)

Never had a bike but a friend of mine says these are great and cost around 100 bucks each at cyclist shops. So, figured this deal might be just for those into Cycling.

Here goes:

Planet Bike 3034-1 Blinky Superflash .5 Watt LED with 2 Red LED Tail Lights (Black/Clear Case)