If you have a Planet Bike Blinky tail light as well as a rear rack on you bike, then the Planet Bike Tail Light Rack Bracket is the means to bring the two together. Fasten this bracket to the L bracket on the rack, attach the tail light, and you're good to go. Means to attach various Planet Bike Blinky tail lights to rear racks Compatible with: Planet Bike Blinky 3,5,7, and Superflash tail lights Requires an "L bracket" that typically comes with a rear rack 25mm between each of the top horizontal holes (center to center)