WOLLENSACK OSCILLO 75MM 1.9 LENS 4X5 CAMERA FORMAT OPTO DYNETICS SHUTTER

It doesn’t say that it is a Wollensack, but all these 75mm 1.9 lenses are of the Wollensack Oscillo brand and model for oscilloscopes.These lenses cover 4x5”. One needs a wide angle recessed lens board.
The glass is in very good and clean condition, nice perfect coating. Shutter works accurate at all speeds, also longer speeds accurate. B & T settings work. 1 sec up to 1/25th speeds one needs to push the lever back to start position. Shutter blades in very good condition.

Lens barrel shows minor signs of prior use and is in very good condition. Shows no scuffing, one small scratch, no dings, no indentations. Aperture setting moves smooth. The elements are in very good condition. No cleaning marks, no scratches, no haze, no fungus, no separation. Shows no dust particles inside. Aperture blades show some wear.Lens has a 39mm diameter screw thread. 50mm screw thread and a 55mm diameter flange.