For my daughter's bike, we already had this light. I cut the clip off of the back. It comes apart, and where the batteries go, I drilled two holes matching her rack, put the bolts through, sealed them with silicone, and mounted it to the rack. Works great, and didn't have to buy a special light. Very bright too, and I used a couple of washers to keep it away from the rack so she could reach her fingers in behind to turn it off after she gets to school.