This is the earlier version 50mm lens for the manual focus Canons. It will work on all of the models, but will not give auto-exposure on the shutter priority models (the AE-1 and A-1 for example).
This one is in good condition and works well. There is a small amount of oil on the aperture blades but they open and close smoothly, it does not affect their function. The glass is clean and scratch-free with no haze, fungus or other problems. The focus is smooth.
Caps are included. Get a deal on a nice lens!