This is a custom-made grip. It was made with a 3D printer. It's a plastic tube that fits the grip section of a Sarasa pen (not an official product, a personal creation). The ballpoint pen itself is not included. Grip only. Operation has been confirmed with c300 series refills. If you're unsure if it will fit your refill, please let me know which refill you'd like to use in the comments, and I'll respond. It will be shipped wrapped in bubble wrap and packing film.