Ditching the traditional tube design of standard writing tools, the bulletproof Ko-Axis Rail Pen has a unique flat, rectangular design emphasizing comfort and easy carry. The skeletonized twin-rail mechanism used to extend and retract the ink cartridge along with the lightweight 6mm body decreases tension on your fingers for fluid action, while making it extremely portable, complementing your compact everyday notebook. The aerospace grade Ti-6Al-4V titanium pen is composed of 24 custom machined pieces and comes with a premium Monteverde D1 ink refill. And according to TEC Accessories, this pen will last a lifetime.