Ditto to the $2 U mount. It only holds 1" diameter flashlights. I found the velcro on the bars to be not a great choice. I recently upgraded to XinTD C8 V5 XM-L2 U2 1A 18650 Flashlight this flashlight and I have to say I really like it for $30. The beam is pretty tight and it's bright if you use 3400 mAh 18650s. I can ride 20 mph and see far enough down the road to feel safe.

Don't be fooled by the $2 price of the U mount. It's a winner. I've been using the same one for at least three years and it's still rubbery and supple. The two fish style velcro mounts are OK for helmet flashlights. Of course you purchase the ones where the two velcros are at 0º not 90º angle.