Just pulled this off an old German folder that I got for $20. A very nice Cooke Triplet. I know the Isco Westar 75mm f2.9 and the Enna-Werk Correlar 80mm f2.9 that also came as options with this camera (Balda Baldix), but could find nothing online about with this particular lens. It turns out to be extremely sharp wide open, with almost no CA, no vignetting on FF, though contrast could be better. Still, quite a nice piece of glass with very nice bubbly bokeh. Optically it is far superior to the famous Trioplan, though the bubbles are a bit less pronounced (which is a good thing IMO).