For a Vivitar 90mm f2.8 macro lens in Canon FD mount fitting.
This goes right down to life size, 1:1 magnification, and you can go closer if you put an extension tube on it.
Focus is smooth.
The iris is snappy, no oil on the blades.
Optically the lens has no haze, no fungus
This is a high quality macro telephoto lens.
Cosmetically, this is in excellent condition.
Can be used on digital with the correct adaptors