It’s undersized in specs, but performs like a full-size yo-yo.
With a full-size yo-yo, I’ve gotten to the point where my own combos flow smoothly. Yo-yoing is fun. I want to spend more time with it. It would be even better if I could carry it around in my pocket. I think reaching for an undersized yo-yo is a natural reaction to that feeling.

But when I actually try spinning a smaller yo-yo, my usual tricks don’t flow as smoothly. It doesn’t spin long enough, the mount isn’t stable, and the bind doesn’t come back. Even though I haven’t changed a thing, just switching yo-yos makes that satisfying feeling disappear. Eventually, I go back to full-size, and I gradually stop reaching for smaller yo-yos.

STEPROUND UNDERSIZE was designed to change that experience.

We’ve brought the high rotational efficiency of the “STEPROUND shape”—established with the STEPROUND FULLSIZE—directly to the undersize model.

Small yo-yos inevitably lose rotational power. Traditionally, the only way to compensate for this was to make the rim heavier, resulting in undersize models that were “heavy and sluggish yet didn’t spin well.”

STEPROUND UNDERSIZE has changed that approach.

Rather than relying on weight to generate spin, it ensures spin through efficient weight distribution and a higher initial spin rate. Because Size D bearings have a smaller outer diameter, the same string length results in more wraps around the bearing, leading to a higher initial spin rate. Furthermore, the combination of a lightweight Size D bearing and an M3 axle significantly reduces the weight of the center section. By designing the rim to be streamlined without being too close to the outer edge, it achieves both ease of movement and tenacious spin. The width is set slightly wider at 44mm, ensuring both easy string catch and sufficient rim weight.

That’s why it releases lightly from your fingers the moment you throw it. The yo-yo responds naturally to your follow-through. Yet, the spin doesn’t falter until the very end of your combo.

The only thing that’s changed is the size. The satisfying feel of an undersize yo-yo remains exactly the same.

On top of that, you still get all the unique benefits of an undersize yo-yo. The lightness that lets it glide smoothly through tight spaces during tricks where the string is densely packed. The portability that lets you slip it into your pocket and throw it anytime, anywhere. The “joy of agility”—something you couldn’t experience with a full-size yo-yo—is layered on top of that sense of security.

There’s absolutely nothing to be afraid of.

The perfect relationship between you and your yo-yo continues just as it always has.

We also recommend it for those trying an undersize yo-yo for the first time.

Recommended for:

Those who have mastered string-to-string tricks with a full-size yo-yo and are interested in undersize models.
Those who have tried undersize models before but didn’t feel they were a good fit.
Those looking for a yo-yo they can carry in their pocket and take with them every day.

---  Quoted from the official website  ---