Join the Pentax 645 mount lens to a Sony Alpha E-mount camera with the Fotodiox Lens Mount Adapter. Along with infinity focus, the adapter lets you adjust aperture manually. For exposure, you can use the manual or aperture priority mode. Lenses without an aperture adjustment ring are stopped down to the lowest f-stop value by default. This Fotodiox adapter fits perfectly to the lens without any gap left between them. The adapter is built from quality metal while the brass mount is plated with chrome.