The vivtar 135mm f/3.5 I have is a hand-me-down from my father that I received with my OM-1 and 50mm f/1.8. Its an old t-mount lens so it lacks automatic diaphragm controls. To stop the lens down you need to set the top ring to the desired aperature, focus the lens in the view finder, and then turn the lower aperature ring to close the diaphragm aperature and then take the picture. Metering must also be done with the diaphragm stopped down.
The lens is quite small and light taking a 47mm filter. The lens has a minimum aperature of f/22. The optical quality is pretty good, but by no means excellent. Its a great prime lens for throwing in a pocket so you have some short telephoto reach. The lens is single coated with a minimum focusing distance of 4.5ft and it is 3.5″ in overall length.
Below is a sample photo taken with the vivitar 135mm f/3.5 lens, probably stopped down to f/5.6
Here is another picture for size comparison of the 135mm large