Jetstream 0.5 Multi-Color/Multi-Function SXR200-05 [5 pieces] Shaft diameter: 2.3mm Length: 67mm Oil-based ballpoint pen refill. These 0.5mm refills are for the Jetstream Prime multi-color/multi-function pens, and are also recommended as gifts. Jetstream is very different from conventional oil-based ballpoint pens, offering a smooth writing feel and quick-drying ink, allowing you to draw clear, dark lines that glide effortlessly. Refills: Jetstream Prime 0.5 Multi-Color/Multi-Function, 5 pieces, SXR20005.24 Please let us know if you would like to change the color.