GOPRO HERO9 BLACK WIDE ANGLE FISHEYE LENS + ADAPTER + HD MACRO LENS | eBay
Use Your Own Lenses on GoPro Cameras! - BACK-BONE
Add lenses to your GoPro with this mod - CNET
Amazon.com : ULANZI G9-5 Housing Case for Gopro Hero 10 9, Aluminum Video Cage with 2 Cold Shoe Mount for Mic and Led Light, Protective Frame with 52mm Filter Adapter, Lens Cap,
Nikon to C-Mount (Iris Control) - BACK-BONE
Adapter for GoPro and LEGO® Technic - 1x3 Beam (ECAV2L9CB) by SevenStuds