Got this from the camera show, and was stupid enough not to check the mount because it was only $10. I looked at the name ring which said Retina-Curtar-Xenon and automatically thought it was a Kodak Retina mount. In any case, Contaflex mount has pretty long lens to film register and I was able to planted inside of a Yashica 50mm f2 lens -- held together with duct tape. It takes pictures, that's all I am saying at the moment.