I saw that Albert Kim had used one on his BetaFPV naked GoPro case (Hero7).
I bought a BetaFPV naked GoPro case and it's fits perfectly with no modification required. It's a friction fit that is not coming off in a crash. Definitely recommend.
While these are good quality filters, they have a bad tendency to have the glass element pop out of the filter ring. This has happened to me on an ND16 and also the UV filter. Sure, the filter ring stays on but if the glass keeps popping out, you’re forced to replace them constantly if you hit them just right after a bump apparently.
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