This is a used 50mm cine lens with an EF mount, made by modifying a Canon FD lens. It has a metal body and is quite substantial (a filter for the front requires one over φ90mm). The front cap is a metal slip-on type and is branded "Vermillion from Fotodiox Pro." Both focus and aperture can be adjusted steplessly. There is no noticeable haze, dust, or fungus that would affect normal use. I have confirmed that it can be mounted and used for shooting on the Canon Eos 5Dmk4, R5 (with a Canon genuine mount adapter), BMPCC6K, RED DSMC1 (Mysterium-X), RED DSMC2 (RAVEN), and RED DSMC3 (KOMODO + Canon mount adapter), but an acquaintance said, "It didn't mount properly on the METABONES Speed Booster." The base is the simple structure of the FD lens era, for better or worse. I don't think it has the processing of current lenses like "to suppress focus breathing..." or "fringe reduction with such and such coating..." For reference, the photos from the 8th image onwards are still images taken with a Canon EOS R5 (+RF/EF conversion adapter) in full-frame. The 1st and 2nd images were taken at the widest aperture (SS1/125, ISO400), and the 3rd image was taken at T22 (SS1/125, ISO640) of a cloudy sky. (↑I took these in an environment where vignetting, fringing, distortion, and dust are likely to appear prominently, so please use them as a reference if you are concerned about those aspects. The rear element moves back and forth with focus adjustment). *This is not a manufacturer's genuine product, and it is a lens from the silver halide era, so please understand that it is sold on an NCNR (No Claims, No Returns) basis. #canon #EF mount #old lens #FD lens #50mm #single focus #cine lens #cinema lens #full size #S35 Focal length...50mm Other features...old lens, with lens hood, with rear lens cap, with front lens cap Maximum aperture...〜1.4