JUST FINISHED A NEW BATCH - now making them out of matte black heat-resistant fiberglass-reinforced polymer: never had any issues with the old material, but this stuff is even better and I love overkill.

Adapter rings to mount modern 5.25" speakers to the rear "shelf" position in a W123 sedan w/o modification to the speakers OR the car itself.

Sized for Rockford Fosgate Prime RX1525x2 speakers. It will *likely* fit other speakers with a 4-hole mounting pattern that can accommodate 135.5mm center-to-center mounting. If in doubt, reach out.

Included:
(2x) Adapter Rings (white in photos for visibility: currently making them in black. you won't see it after installation)
(2x) sets new mounting screws for the speakers
(2x) sets new mounting screws for the grille

NOT INCLUDED, you'll need to provide:
Grilles: you will need to provide your own, original-specification ones. They're available on eBay.
Speakers: as mentioned, these are sized to fit Rockford Fosgate RX1525x2

Possible fits for:
W123 coupe
C107
W116
I haven't tried it, but they seem to use the same outer grille, so I suspect they would work? Feel free to reach out and we can figure it out together. :)