This lovely M39 mount early-version Schneider-Kreuznach Componon 135mm f/5.6 darkroom enlarging lens comes with its retaining ring. There are a couple of light scuffs on its exterior. There is a slight dent in the metal around the rear element grouping. Its aperture is very smooth, and its glass is free of any fungus, haze, or separation. There is no oil on its aperture blades.
