About the Montblanc 139, they exist with short window and long window , also were they made with celluloid and ebonite cap. I have some questions : 1. Did the celluloid version have short windows and the ebonite versions long windows ? Or are there short windows in ebonite and celluloid, idem fot the long windows? 2. Where both versions in production at the same moment? Or was there a change in choice of used materials during the production of the 139?