Free 

This design uses a single 8in zip tie for attachment to the helmet. I also put a single strip of electrical tape on the side of the mount that contacts the helmet to help keep it from moving around while riding.
Printing Instructions
Rafts: No
Supports: No
Resolution: Any, I used 0.28
Infill: 50%
Wall Count: 4
Top/Bottom Layers: 4
Filament material: PLA
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