GoPro Hero Session Mount with ND Filter slot for Martian II frame

Features
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* 25˚ angle (feel free to ask for other angles)
* 29x26x1.1mm space for nd filter. I use those square ones (~$10 each) for hero black and pop out the nd filter to place in here.

changelog
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* v2 : closed in font hole space a little, mainly b/c I was getting layer splitting w/ my 3d printer so wanted the added connections to combat it.