These are Rodenstock Rodagon enlarging lenses that were probably used on an automatic printer in a commercial lab. The aperture on the lenses is fixed with a small hex head bolt. I assume the aperture will be free to move if the bolt is removed. In any case, they look like regular enlarging lenses in every other respect. One of the lenses has a retaining ring screwed into the front. I've tried removing it without success. I know it comes off because I removed a similar retainer on the other 2 lenses. The glass is great on all the lenses. I have rear caps for the three, but no front caps. I'm "giving" them away for $75 plus shipping....