TEC Accessories Ko-Axis Rail Pen Black. 29" overall. Pocket clip. Rectangular shape for writing comfort. 6mm low-profile body. Embedded micro socket provides a no hassle refill replacement that does not require tools. Compatible with common D1 "multi-pen" (TEC02 TEC03) Fisher Space Pen (FP171112 FP171211 FP171419) and Rite in the Rain (RITR37R) refills. No possibility of accidental ink retraction during use. Anti-roll design. Assembled from 24 individual custom machined components. Black finish aluminum body with stainless guide rails. Boxed. Specifications for TEC Accessories Ko-Axis Rail Pen Black: Manufacturer: TEC Accessories Additional Features: Pocket Clip Length: 4.29 in Overall Length: 4.29 in Package Contents: TEC Accessories Ko-Axis Rail Pen Black