I bought two. They are processed very clean, the surface quality is very good, the thread is cut cleanly and smoothly. The bayonet is like an original lens. I measure 26,12mm to 26,14mm. The perfect measure would probably 45,5MM - 19,25mm = 26,25mm. Infinity is thus achieved. Who wants to have it perfect, laying a paper a ring in the adapter. Laser paper of 80 g / m² has a thickness of one tenth of a millimeter. So, five fingers crossed! Possibly the cheapest adapter is the best. The price may at any lens a, then eliminates the Schrauberei. Do not forget the cover!
Previously dominated the company cutting a thread with an exact beginning. All lenses with M42 prove it.
