About This Pen: This Montblanc Meisterstuck Solitaire Doue Signum M23367 Pen has a rollerball writing system. It features a special design on its black precious resin barrel, complemented by a platinum-plated cap. Both clip and fittings are platinum-plated. The three platinum-plated rings on the cap is embossed with the Montblanc brand name.