Summary

Just a simple hat clip I created for the GoPro after being unable to find one. The brim should be about 4mm thick for it to fit the best.

I used a modified version of this GoPro mount in order to attach the GoPro to the hat clip:

http://www.thingiverse.com/thing:276426

I attached the STL and the Blender file that had already been cut since it was a simple cut and I didn't save it pre-cuts.