Uni Jetstream Karimoku Tano Pen 4&1: A Limited Multi-Pen With Real Wood Charm

Introduction

The Uni Jetstream Karimoku Tano Pen 4&1 is a collaboration between Uni, maker of the Jetstream line that reportedly sells more than 100 million pens worldwide each year, and Karimoku, a furniture brand known for design and build quality. Released on November 5, 2024 as a limited-quantity model, it comes packaged in a wooden-textured box with an embossed surface and the word Limited printed on the front, signaling from the start that this is a special release.

Priced at 3,630 yen tax included, this edition dresses the familiar 4&1 format, which combines black, red, blue and green ballpoints with a mechanical pencil, in a fresh color-painted treatment themed around adult building blocks. The version covered here is the Grey Green of three colorways, alongside Pink and Indigo Blue.

Design and Build

The standout feature is the grip, which uses wood from Karimoku furniture production. Specifically, it is made from offcuts and trimmed pieces left over when wooden furniture is made, material that would otherwise be discarded, given new life as a writing instrument. The paintwork is selected from the color chart Karimoku actually uses for its furniture, so the palette feels cohesive and mature rather than decorative. Unlike some Karimoku collaborations, the grip here carries no Karimoku logo, letting the painted finish speak for itself; if you would rather enjoy the natural wood grain, the standard Karimoku collaboration models remain the better pick.

The barrel uses a resin body with a soft-feel style coating. In hand it feels smooth and slightly tacky in a good way, offering grip without the rubbery stickiness some soft-touch finishes have. The barrel color is officially unified in grey across all three colorways, though an optical illusion makes the Grey Green look faintly greenish while sitting in the packaging, enough to spark a small debate with stationery shop staff about whether the barrels actually differ. The nose cone shares the same painted finish and adopts the rounded, curved shape also seen on the Pure Malt and Inside models, which adds a friendly, endearing character to the silhouette.

Finishing details are consistent: the center ring, clip and all metal parts are matte black with no plating anywhere, so the entire pen has a non-glossy, understated look. Japan is marked on the side, and the barrel carries engraved maker and series markings. Clip tension feels about average. Dimensions are 148mm in length and 24.8g in weight, with a 13mm grip section diameter, and the balance point sits low, which helps the pen feel settled in the hand.

Writing Performance

The ink performance is exactly what Jetstream fans expect: smooth, easy-flowing and consistently pleasant to write with. The wooden grip, even painted, still communicates a hint of wood texture under the fingers, which adds warmth to long writing sessions.

The 4&1 mechanism covers four ballpoint colors, black, red, blue and green, plus a mechanical pencil, making it genuinely practical for color-coding notes or planner work. The initial refill is the SXR-80-05 at 0.5mm, using the standard Jetstream ink rather than the newer Light Touch formulation. Replacement refills cost 110 yen each tax included, and Light Touch refills are also compatible if you prefer that lower-friction feel.

The knock mechanism is a slide type, with minimal color markings on each slide section, a restrained touch that preserves the overall design. Sliding action is positive with a satisfying knock feel. The mechanical pencil advances by sliding the clip, and an eraser is built into the top section. One small quirk to note: there is slight wobble at the tip during writing, though it sits well within acceptable range and is on the lower side compared with many multi pens.

Things to Consider Before Buying

The most legitimate complaint is the clip position during writing: it can press against your hand as you write, and over a long session that becomes a genuine annoyance. Notably, the Jetstream Light Touch multi pen already solved this with a shortened clip, so it would be welcome to see that improvement carried into this series as well.

Barrel thickness is the other consideration. At 13mm across the grip, this is a substantial pen, and writers who dislike thicker barrels may find it tiring. Everything else, from the matte finish to the color matching, feels carefully judged for a limited-edition release.

Buying Advice

For anyone who values looks, the concept alone is admirable: furniture offcuts reborn as a pen, finished in colors drawn from real furniture production. The pleasant grip, good weight balance and stable, easy writing round out a package that feels worthy of its limited-quantity status.

Because it uses four ink colors alongside a pencil, it suits tidy note-taking, planner organization and everyday desk work alike, and it is the kind of multi pen that works for students and working adults across a wide range of situations. Since it is a limited-quantity release and this series is quite popular, anyone interested should pick one up sooner rather than later; it may already be sold out in some places.

Conclusion

The Uni Jetstream Karimoku Tano Pen 4&1 blends a sustainability-minded concept with beautiful muted colors and dependable Jetstream writing. Aside from the clip contact during writing and the thicker grip, there is little to fault, and for fans of limited stationery collaborations it is an easy recommendation while stock lasts.