UNO 24 Edition 15 Review by Beans&Bezels

Klaus Botta, 15.04.2024

BOTTA is a German watch brand nestled in the town of Königstein, and was established by the designer Klaus Botta. Motivated by a commitment to design simplicity and tranquility, BOTTA embraces the essence of minimalism, perfectly embodied in their single-hand watch models. Since Klaus Botta introduced the UNO in 1986, an early modern interpretation of the one-hand wristwatch, the brand has evolved to embrace this design ethos. Rooted in the Bauhaus design principles, BOTTA not only embraces simplicity and functionality but also critically evaluates the often cited alignment of other watches with Bauhaus ideals, suggesting a deeper, more authentic commitment to these design principles. That said, BOTTA isn’t afraid to dabble in more avant-garde designs either, and their Clavius model maybe my favorite of their entire catalog given its futuristic design.

In this review, I will dive into the Uno 24 Edition 15, a model that colorfully captures the brand’s philosophical underpinnings with practicality. This particular variant is equipped with a quartz movement and encased in a bold 45mm diameter. It’s noteworthy that this model is also offered as an automatic version or in a more compact 40mm case size option. This model is priced at $826, including VAT.



While the dial might garner immediate appreciation for its accessibility and aesthetic appeal, it’s the case that I enjoy most. With a diameter of 45mm and a lug tip to lug tip measurement just slightly over that (and a lug hole to lug hole measurement well under that! at only 35,5mm), the clever design of the case and lugs makes for a distinctive and memorable presence on the wrist. The case’s slim profile, just over 9mm thick, is crafted from TRI-Titanium and this version has a PVD coated bezel.


The execution of the case design is outstanding, with a pseudo-lug-less appearance that still presents beautifully crafted lugs. The perfectly round case silhouette is complemented by a complex array of angular surfaces that converge seamlessly into a perfectly flat caseback. The watch is equipped with a double domed sapphire crystal, which, together with ample anti-reflective coating, ensures excellent legibility under various lighting conditions.


Despite its relatively small size, the crown is thoughtfully designed to be easy to grip and operate. Additionally, the watch has a water resistance rating of up to 50m, which is quite sufficient for everyday wear and for a watch of this genre. In summary, every aspect of this watch’s case reflects a harmony of excellent design details, blending creativity with a subtle elegance that I find very compelling.



The dial immediately captivates with its striking black and yellow 24-hour split, evoking the visually engaging and romantic function of a day/night indicator. This color scheme, apart from being aesthetically pleasing, significantly enhances the dial’s readability and brings a unique flair to the timepiece. The dial has quite a few meticulously crafted details, including a sloped chapter ring/minute track accentuated by four cantilever style applied markers at the cardinal points. The division of time is thoughtfully marked by large white ticks for each hour, with smaller and medium ticks denoting ten and thirty-minute intervals, respectively.


A well-integrated date window at 6 o’clock, featuring a color-matched date wheel, complements the dial’s symmetry. The color coordination, yellow on black for the daytime section and black on yellow for the nighttime section, with cardinal hours in white text – deeply satisfies my OCD. The brand’s logo is printed in black beneath the 12 o’clock index, maintaining the dial’s balanced aesthetic.

The single hand extends to the dial’s outermost marking ensuring legibility, and a white circle on the hand’s stack further contributes to the dial’s symmetry, enhancing the visual harmony and making it a true delight to observe. Overall, the dial’s finishing and quality control are commendable, with only minor issues like a few stray paint particles, which are a small concession in the context of a mostly printed dial.




This watch is powered by the Ronda Caliber 515.24H, a GMT complication quartz movement. Interestingly, the brand has modified this movement, repurposing the GMT hand to function as a 24-hour single hand. This adaptation mirrors the brand’s approach to their automatic models, which utilize the elabore grade ETA 2893-2 movement, similarly modified for a singular hand operation. The choice of a quartz movement, particularly for a timepiece that lacks dynamic (ticking or sweeping) elements, does not detract from its value or appeal. Indeed, in the context of this watch’s design and functionality, opting for the quartz variant seems entirely fitting if you’re on a budget. Conversely, for watches like the Clavius it only makes sense to go with an automatic, as they do.


On The Wrist

When I initially requested to review this watch, I had my sights set on the 40mm version. However, the brand suggested I give the 45mm model a go instead—a recommendation I approached with a fair bit of skepticism. In retrospect, this turned out to be a wise decision. Despite its seemingly large 45mm case diameter, the watch’s pseudo-lug-less design contributes to a surprisingly compact fit on the wrist. The slender profile of the case, combined with the use of lightweight material, further enhances its wear-ability.

On my roughly 6.75″ wrist, the watch sits comfortably, making me believe that anyone with a wrist size of at least 6.25 – 6.5″ should find it suitable. I suspect that there’s a potential trade-off in legibility when downsizing to the 40mm version, so I might be inclined to recommend the 45mm model for those who can carry it. The watch came with a saddle leather strap that has an interesting texture and good craftsmanship—qualities not often found in most stock straps. I also like the stainless steel link bracelet option, which I imagine would complement the watch’s design beautifully.


Wrapping Up

This watch stands out as a product of meticulous design thought and attention to detail, which shouldn’t come as a surprise given it’s fundamentally design forward DNA. It’s one of those pieces that showcases the care and consideration put into every aspect, something I particularly appreciate while reviewing a watch. The build quality and finishing are commendable. The dial has a lot of interesting details, supported by good quality control. The concept of a single-hand watch might initially seem unconventional to many prospective watch buyers. However, for those willing to try something different and something a bit more laid back, this watch is a good option. It challenges the traditional expectations of a watch while providing a unique, minimalist aesthetic. Lastly, for those leaning towards the automatic variant, I suggest giving the quartz model serious consideration. Not only does it offer a significant cost saving, but it likely delivers the same visual experience.



Many thanks to @beansandbezels for providing the Review and the images.

Leave a comment

Additional posts

The History behind the iconic UNO 24 Anniversary Edition-15

Klaus Botta explains how the unconventional idea for a 24 hour one hand watch came to life and ho...

UNO - The Original among the Single-Hand Watches of the Modern Era

The Origin: Klaus Botta developed the concept of the UNO, the first single-hand watch of moder...

Good Design Award for TRES 24 from BOTTA

The TRES 24 by BOTTA convinces with an unconventional display principle paired with outstanding d...

TRES 24 Automatic - as individual as time itself

The 24 hour watch TRES 24 Automatic is the right watch at any time. The pleasantly decelerated mo...

The new TRES 24 Quartz 40 mm – 24 hours, 60 minutes and C seconds

We at BOTTA like to give time extraordinary, but always logical shapes. This is also true of the ...

UNO 24 plus titan

The UNO 24-Plus models with a diameter of 45 mm now have a completely redesigned, unique titanium...