M42 Reversing Rings

Allows you to reverse mount an M42 lens. If the lens has no A/M switch (auto/manual), you will need to hold down the pin on the end of the reversed lens to actuate the diaphragm. Use SRB~Griturn SPACER RINGS between the camera and the ring to increase magnification. Use SRB~Griturn STEPPING RINGS to use with a lens having another size filter thread. These adaptors allow ANY lens with the appropriate filter thread to be reverse mounted.