If you have a SLR or DSLR camera and other maker/mount lenses, the Fotodiox Mount Adapters allow you to use your lenses on the film/digital camera body. Sharing lenses has some distinct advantages. Certain prime lens just can't be replaced, and you save the cost of purchase on new lenses. Fotodiox offers a range of adapter from large format to smaller format digital adapters. Adapting larger format lens to smaller format sensors (i.e: large format to medium format, medium format to 35mm, 35mm to micro 4/3) provides excellent edge-to-edge sharpness. The smaller image field helps minimize the effects of lens distortion and aberration by using the 'sweet spot' or center of the larger lens image circle.This Fotodiox lens mount adapter is made with high standard precision. It&rsquo. This lens mount adapter allows a Leica 50mm/75mm M39 Mount Lens to fit on a Leica M camera body with appropriate viewfinder frame lines on enabled camera body.Although the lens will fit physically, automatic diaphragm, auto-focusing, or any other functions will not operate correctly while using this adapter. In this case "stop-down mode" will need to be used when metering since the lens does not have the ability to have its aperture controlled by the camera body. You can shoot with manual mode or aperture priority mode.Compatible Cameras (including, but not limited to): Leica M3, M2, M1, M4, M5, CL, M6, MP, M7, M8, M9, Hexar RF Epson R-D1, 35mm Bessa, Cosina Voigtländer, Minolta CLE, Rollei 35 RF, Zeiss Ikon, Ricoh GXR A12 M-Mount ModuleNote: The product pictured may have slight differences in appearance from the actual product such as color, font style, and/or other cosmetic changes due to improvements in design.Regarding lens alignment, some of our adapters do have a ring that can be adjusted so the lens is aligned to the 12 o'clock position on the camera. But because this adapter is one, solid piece, that adjustment is not possible. We do understand that it's inconvenient for the lens to be misaligned, but as long as the lens mounts onto the camera correctly, this will not ultimately affect the functionality of the lens itself.