Dauntless
Contributor
Aluminum 1/16" x1" strip long enough to make the holder + 1/2" PVC Coupler that is ~1" in diameter as a form (May use the light itself also but may scratch it up) + a bicycle thorn proof inner tube, thicker on one side (go to local bike shop and they may give you a flat tube for free) take hands and pliers to bend around the form, leave legs, slide inner tube over formed strip, thick side to light, drill 5/16" hole and then may screw into a ball adapter.

A little paint makes it look better

A little paint makes it look better