Kaiyu Plus Sellar Ballpoint Pen Review: Elegant Design with One Notable Trade-off

Introduction

The Sellar ballpoint pen is a new release from Kaiyu Plus, a young stationery brand that is clearly building its lineup with a lot of care. Priced at 3,300 yen including tax, it launched alongside a matching drafting mechanical pencil, though the two take noticeably different design directions. After spending real writing time with the Sellar, the honest verdict is that the potential here is very high and the writing feel is genuinely pleasant, but one small detail during writing did not fully come together.

Who This Pen Is For

The Sellar suits people who want an elegant, design-forward everyday pen with a smooth gel refill rather than a scratchy ballpoint feel. It is also a good match for writers who care about balance and grip stability, since the weight sits near the center and the grip holds firmly without slipping. If you want a completely vibration-free tip or a flashy primary color, this may not be the right pick.

Packaging and First Impressions

Out of the box, the pen arrives in a frosted translucent package with the product name printed in white at the center. The frosted surface lets you see the pen inside, which is a genuinely stylish touch. Inside, a plastic sleeve holds the pen in a firm, sponge-like foam that has been cut out to the pen’s shape, keeping it securely fixed during transport.

Kaiyu Plus also released a drafting mechanical pencil at the same time, but the Sellar clearly follows its own, more elegant direction.

Design and Build Quality

The Sellar comes in four colors: Ceramic White, Morning Blue, Amethyst Grey, and Pastel Pink. All four are white-based with very light pastel tints, so there are no vivid primary colors in the lineup. The barrel is resin, and the first thing that stands out is the texture: it feels remarkably like lacquerware, in the best way. Compared side by side, the Grey version reads as slightly more premium than the White, and the White itself can feel a touch cheap.

The shape is distinctive. The barrel swells in the middle and tapers toward both ends, which gives it a fashionable silhouette. The product name is printed in white on the center of the barrel, with the maker name on the reverse.

The grip section has fine vertical grooves that provide real traction. It feels more secure in hand than expected, holding firmly without any slipperiness. The grip and front cone are a single integrated piece, which gives the pen a sense of precision assembly. Removing the grip reveals a brass weight inside, added to give the pen stability and keep the balance from feeling too light.

Nib, Refill, and Knock Feel

The initial refill is a 0.5mm gel cartridge, and because it uses the G2 format you can swap it for a Jetstream refill if you prefer a different writing feel. The front cone has very little tip play: not quite at the level of a frictionless knock zone, but for a knock-style ballpoint this lack of wobble is impressive.

The clip is metal, painted gold on all colors, and short enough that it does not dig into your hand while writing. It is also a swinging type, so it opens lightly. The knock mechanism has a narrowed base with a widened thumb contact area, making it easy to press. The knock feel is light, though there is noticeable play in it.

Specifications

The Kaiyu Plus Sellar measures 142mm in length, weighs 21.6g, and has a maximum grip diameter of 12mm. The balance point sits near the center of the barrel, which contributes to the stable, controlled writing feel.

Writing Performance

Despite being a gel refill, the Sellar writes with no scratchiness at all. Lines flow smoothly across the page with a consistently pleasant feel.

The tip play itself is very small, but because the grip and front cone are integrated with a brass weight built in to raise the center of gravity, a faint tapping vibration from the tip can be felt at the fingertips at certain writing angles. It is a small thing, but it is the one detail where this otherwise refined pen falls slightly short.

Things to Consider Before Buying

The strengths are easy to list: the design is genuinely stylish, the writing feel is excellent, the balance is well judged, and the grip delivers stable, slip-free writing. The G2 refill format adds practical versatility, and the construction feels precise for the price.

There are three caveats worth weighing. First, that faint tip vibration during writing at certain angles, even though the actual tip play is minimal. Second, the White version in particular can feel a little cheap, partly because of the matte barrel texture; a glossier finish would arguably feel more premium. Third, the white printed product name on the barrel does cheapen the look somewhat; an engraved mark would have made a much stronger impression. The parting line along the barrel side is visible, but it is cleanly finished and within acceptable range.

Buying Advice

If you are drawn to the design, choose a color other than White if possible; the Grey version felt the most premium of the range. Buyers who prioritize a totally silent, vibration-free tip should try it in person first if they can. Everyone else gets a well-balanced, smooth-writing pen with a refill system that can be tailored to personal taste.

Conclusion

The Sellar shows a new brand putting real care into its craft, and that effort comes through in the elegant design, the refined writing feel, and the thoughtful weight tuning. The fine tip vibration during writing is a small miss in an otherwise polished package, but it does not change the overall picture: this is a pen with high potential, and one worth buying if the design speaks to you. Kaiyu Plus is a brand worth watching.