Be aware that the Industar rangefinder ring does not always give accurate focussing with Canon Rangefinder cams (And Leica Cameras too). If you get one it would be best to expose a roll of film at close and distant focussing points to check if all is OK, before parting with a lot of cash or a guarantee you will get your money back. I don't know if they can be adjusted for better accuracy but somehow I doubt it.