Sakura Craft Lab 004
Design forward Japanese machined pens. All are twist action. The 004 is the only multi-pen. It’s a 2+1 or 2 inks + 1 pencil. The action has a hard stop in the twist, it’s not a continuous rotation as some other multi-pens have.
Variants: Each numbered pen edition is very different from each other. Each comes in a range of colors. Some come in aluminum or brass. The pictured version is a brass grip and aluminum body.
Refill depending on variant: The 004 multi-pen takes D1 refills. Most take proprietary gel refill in various lengths. Pen specific refills are available from the factory. A known hack is the Sakura Ballsign ID refills fit when cut to length.