The Cine Mod Auto Sears (Rebranded Rikenon) 50mm f1.7 is a standard, high-quality lens with a maximum aperture of f/1.7. It is compatible with M42 mounts and Canon cameras and has been modified with focus gears and a de-clicked Canon EF adapter. The lens was manufactured in the 1970s in Japan and is made of solid aluminum.
Test shots taken with Sony A7R ii (using EF to Sony E adapter). The rendering is quite nice, very vibrant colors and really unique bokeh.