This listing offers a Bayonet-I to 49mm Adapter Ring designed for TLR cameras. These adapter rings are compatible with various TLR camera models, including:
Bayonet mount accessories are becoming increasingly scarce, but with these adapter rings, you can easily use standard 49mm filters, hoods, and other accessories with your cherished camera. It's a simple solution to a challenging problem, and you can also use filters of different sizes with additional stepping rings.
The adapter rings have been 3D printed from PLA plastic. They don't have threads; the filter securely snaps into place with a simple push (some light sanding may be needed on the inner edge depending on the filter brand). These rings have been tested with Hoya filters and Kenko.
You can attach a metal step-up ring to gain access to a threaded mount. Please note that this listing includes the adapter ring only.