The adapter came from a saker. I believe it will also fit the chimera. Selling as a lot $200.

1 adapter
2 30cal brakes 5/8-24
1 556cal brake 1/2-28

All parts are in good condition. Never had an issue with the mounting system. I really liked the one hand operation. I got frustrated trying to find muzzle devices and switched to keymo. Cross listed. Came here because lack of interest on arfcom. Link to a Google pic

https://photos.app.goo.gl/LANGQb1D4PRJK4Zh9