Hi Terry,
I don't see this mark on any of the lists. It looks like I. I. C. Kollmann, Quakenbruck. I assume it's a distributor mark on an otherwise unmarked short, stag grip dress bayo. The seller thought it could be luft because there was a luft base near Quakenbruck. The frog does look to have a brown tinge to it. What do you think?
Thanks, Lance