This is a well used but still good condition Mamiya 645 55mm f2.8 S lens, including both caps.
This lens in is perfect mechanical condition. No problems at all, aperture really fast without any sticking. This lens has a damaged filter ring, plus a few coating damage marks on the front element but no scratches, haze, separation or dust; optically will work excellently. This is still a really usable lens.
This is the very highly regarded S model – the later much improved N version optics in a metal body – perhaps the best combination you can get. This one has been heavily used but still does the job. Far cheaper (as in well under half price) than a perfect example!