The file 'GEPRC Naked 9-12 For Use TELESIN ND 3D Printer Model' is (stl) file type, size is 9.6KB.
Print it in TPU, put it around the lens of the Naked GoPro and then put your Telesin ND filter on top. The fit is tight, and I have tested a couple of "hard landing" and the filter stays put.
