Uni Jetstream Prime 3&1 Multi Pen Review: Premium Quality, Minor Trade-Offs

Introduction

Uni’s Jetstream Prime line sits above the standard Jetstream range, and the latest addition is the Jetstream Prime 3&1 multi pen. It packs three ballpoint colors and a mechanical pencil into a slim body, and it replaces the earlier Prime multi pen at a higher price of 6,050 yen, up 550 yen from the previous model.

First Impressions

The pen arrives in a bright mint-green package, distinct from the orange packaging of the Jetstream Prime single-color model. Inside, there is even an instruction manual, which is easy to overlook.

The old Prime multi pen featured a jewel on top of the clip that many found cheap-looking, and opinions were sharply divided. That gem is gone now, leaving a much cleaner silhouette while the core design carries over. The all-black finish looks genuinely refined, and the lineup includes two colors: dark navy and black.

The barrel coating is matte, matching the Prime single pen, with a very smooth feel in the hand. Even with dry fingers, it does not feel slippery. The distinctive lower barrel that supports the upper section remains, and small color labels printed on the barrel are a nice, understated touch, with Jetstream branding on the underside.

Writing Performance

The Prime 3&1 combines black, red, and blue ballpoints with a pencil mechanism. Ballpoints come in 0.5mm for the dark navy and 0.7mm for the black, while the pencil is 0.5mm in both colors. Despite carrying four functions, the barrel thickness is nearly identical to the single-color Prime pen.

The writing experience is where this pen earns its price. The tip stays remarkably steady, and the 30.2g weight adds a reassuring stability. The ink is the traditional Jetstream formula rather than the light-touch version, and the 0.7mm option is wonderfully smooth.

The pencil works with a normal knock action, though it has the slightly floaty feel typical of multi pens. Even so, tip wobble is minimal, which speaks well of the overall build quality.

Design and Build Details

The Prime 3&1 uses a twist mechanism. Twisting the barrel extends and retracts the tip, and the rotation is continuous in both directions with no dead ends. The tip locks when extended but does not lock when retracted. The twist action has a somewhat loud, clunky sound compared with lighter, smoother multi pens, which is worth noting.

The barrel separates into three parts, likely using different materials for each component, similar to the Prime three-color ballpoint. The initial refill is the SXR207, a metal-bodied Jetstream refill in the widely used D type, so replacements are easy to find.

The clip is a slit clip that extends far down the barrel, closer to the three-color ballpoint design, and it feels firm. Twisting open the lower section reveals a built-in eraser, and the screw there uses an O-ring seal. Specifications: 139mm total length, 30.2g weight, and a maximum barrel diameter of 11.5mm.

Things to Consider Before Buying

The center of gravity sits toward the upper body, which contributes to the stable, planted feel when writing. Combined with the quality of the finish, it genuinely feels like a pen from a premium line.

There are two quirks to weigh. First, the twist mechanism makes a noticeably louder ratcheting sound than some competitors. Second, during writing, the step between barrel sections sits against your hand, and the clip can touch your fingers as well. Until you get used to it, that barrel step can be mildly irritating.

Buying Advice

At 6,050 yen, this is not an impulse purchase, but the quality justifies the price if a four-function premium pen fits your daily routine. The Prime series is now complete with this release, so anyone who has not tried it yet can compare the single-color pen, the three-color ballpoint, and this 3&1 model to find the best fit.

Conclusion

The Jetstream Prime 3&1 delivers an excellent writing feel, good weight balance, and a versatile D-type refill, wrapped in a clean and refined design. The loud twist action and the barrel step during writing are the main compromises. For those willing to pay the premium, it is a high-quality multi pen that lives up to its price point.