This is a Canon 50mm f1.4 S.S.C. manual focus lens in Canon FD breech lock mount.
This is a wonderful lens with great character. It's a standard 50mm focal length that's usable for a wide range of applications and with the aperture opening up to f1.4, you don't need much light to take advantage of this lens. I've used it in the dim NYC subways with no problem.
Wide open, it is a touch soft and dreamy but can be used to your advantage. Stopped down a touch it gets sharper and behaves predictably.
It's a great lens. I've used it on my Fuji which is a 1.5x crop factor giving me a wonderful portrait lens with great bokeh capability. I've used it for street photography, portraits, and indoor documentary type photography.
Its a very capable lens and I've really enjoyed using it.
Comes with a 55mm Canon UV filter, front and rear Canon caps.