Monochrome Watches
An online magazine dedicated to fine watches

The SNGLRTY Blue Steel OHI-4 and Its Original Display

A single hour hand continuously synchronizes with a minute disc on a clever, innovative dial.

| By Erik Slaven | 7 min read |
SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

Single-hand watches are nothing new, albeit still something of a rarity. MeisterSinger is undoubtedly the best-known brand to embrace the style, but many others have toyed with the concept. SNGLRTY has devoted its entire portfolio to single-hand watches, but all display both the hour and minutes via a clever, patented design. A common way to do this is with a jumping hour like the MeisterSinger Salthora Meta X, but SNGLRTY has figured out how to have a minute disc continuously synch with the hour hand, and it’s an industry first. We go in-depth with the SNGLRTY Blue Steel OHI-4.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking


Several years ago, Stephen Mansfield and Daniel Blunschi began brainstorming over drinks about a single-hand watch design. The ultimate goal was to create something that hadn’t been done before, where a single hand could show both the hour and minutes simultaneously. Brands have gotten creative with a single hand showing both, like Konstantin Chaykin with the Genius Temporis that will temporarily move the hand to show minutes via a pusher.

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Steve and Daniel had another idea and have a minute disc rotate counterclockwise to always show the minutes through an aperture on the hour hand. A reverse gear, if you will. Daniel has over 30 years of watch industry experience. Steve has an engineering background and the two combined ideas of watch movements and engines with gearboxes (hence the reverse gear idea). A final concept was born.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

Following extensive research, both concluded that the idea was unique and didn’t exist. “Present time on a single line like a digital watch, but on a mechanical watch.” The concept was nicknamed OHI – One Hand Indication – and the two got to work. Daniel focused on turning the idea into reality while Steve worked on securing a patent. Twenty prototypes were made and kept accurate time, validating the design. After an initial rejection, the two worked with their attorney on a comprehensive rebuttal and were ultimately granted a patent. It was time for a name, one that described how time comes together at a single point, and “singularity” seemed most appropriate. Of course, it needed to be jazzed up a bit, so SNGLRTY became official.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

There are two collections in SNGLRTY’s portfolio, OHI-2 and OHI-4, with the first having no date and an accuracy of +/-12 seconds per day and the second having a date, multiple movement decorations and an accuracy of +/-4 seconds per day (above the COSC standard). The Swiss movements have an external module, of course, which makes the unique setup possible. It’s only 1.2mm in height, which is thinner than the 2mm norm and is flexible enough for both current and future collections. There’s even a seconds indicator in the form of a small, vintage compass pointer that’s more designed to show that the movement is running. It all culminates in a unique, eccentric design that’s also very functional.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

A Dial Like No Other

At first glance, the dial may come across as a conventional single-hand design with an exposed date wheel (like the MeisterSinger Pangaea Day-Date), but that’s certainly not the case. A date window already sits at 6 o’clock, so the disc in the centre is for minutes. As the hour hand slowly makes its 12-hour cycle, the minute disc runs counterclockwise in perfect synchronization, always showing the correct minute through the hour hand’s aperture. And the compass-looking seconds “hand” in the centre is again to show that the movement is running, although seconds can also be tracked.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

The watch we have on hand is called Blue Steel and is a customized OHI-4 model. SNGLRTY offers colour customizations via the website or over the phone with approximately 3,000 possible variants, not including strap options. This includes the outer hour ring, hour Arabic numerals, minute ring, centre plate, seconds ring and hour hand. Just about everything is configurable, except for the case.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

Blue Steel has a sunray blue hour ring with white Arabic numerals, a black minute ring with white numerals and indexes, a silver central plate with Côtes de Genève and a blue hour hand with a white tip. Plenty of pre-configured OHI-4 and OHI-2 models are also available. The hour numerals and tip of the hour hand are coated with Super-LumiNova. The dial has two levels with the hour ring above the minute disc and central elements, so there’s a nice sense of depth. Although this is a single-hand watch design, it actually reminds me of a regulator with the hour hand doing the heavy lifting (in lieu of a central minute hand). Everything else sits in separate registers. Of course, in this case, hours and minutes converge, so you’re reading both together.

Overall Design and Case

The SNGLRTY Blue Steel OHI-4’s dial steals the show, but the stainless steel case complements it well. It’s very wearable at 40.5mm in diameter and 11.8mm in height (47mm lug-to-lug) and easily slips under a cuff. A double-domed sapphire crystal has no less than seven anti-reflective coatings, and they’re very effective. Reflections are minimal indoors and outside, which is important as you need to clearly see the minute numerals.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

Flip the watch over and the caseback is secured with four hex key screws, and a smallish mineral glass window displays most of the automatic movement. There’s a rare engraving on the back as well – the official patent number. You don’t see that every day. The lugs have a sizeable arch and are seamless with the case sides, and secure the strap with exposed hex key screws. The Saffiano black 21mm strap with deployant clasp is one of seven options, including a steel bracelet. Water-resistance is rated at 100 metres.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

Swiss mechanics

Powering the SNGLRTY Blue Steel OHI-4 model is a Sellita SW300-1, an alternative to the ETA 2892 and 1mm thinner than the SW200 calibre. The height is necessary to accommodate the specialized module, itself only 1.2mm, and keep the watch case at a slim 11.8mm height. This SW300-1 variant is a premium grade with a chronometer standard, accurate to +/- 4 seconds per day. It’s also rhodium plated with perlage and Côtes de Genève. It has 25 jewels, beats at 28,800vph (4Hz) with a 42-hour power reserve. Functions (with module) include central hours, counterclockwise minutes via a rotating disc, central seconds and date.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

Final Thoughts

It’s great to see small independent brands pushing innovative ideas. Recent examples of this include the Humism Rhizome Automatic, and Vanguart Watches Black Hole Tourbillon, and SNGLRTY has a design unique enough to be patented. I’ve always been a fan of MeisterSinger and other single-hand designs like the Umbra by Solar Lab Co. (itself with a rotating disc), but SNGLRTY takes things to the next level. Jumping hours are an adequate and desirable way to show both hours and minutes on a single-hand dial, but the presentation of “time on a single line like a digital watch, but on a mechanical watch” is a refreshing change of pace.

This isn’t a novelty or horological sideshow, either. The SNGLRTY Blue Steel OHI-4 is refined, well decorated and performs with chronometer accuracy. The dial is both familiar and a bit foreign as it kind of resembles the MeisterSinger Pangaea Day-Date, but with very different functionality. New concepts like this don’t always land, but SNGLRTY has really pulled it off with an intriguing and well-thought portfolio.

SNGLRTY Blue Steel OHI-4 patented display watch independent watchmaking

The SNGLRTY Blue Steel OHI-4 retails for USD 4,390, but the OHI-4 collection fluctuates by around 140 depending on added Super-LumiNova and specific colours. The pre-configured Blue Monday, for example, is USD 4,250. It’s certainly not cheap but also reasonable for such an innovative, patented design with a custom module. If you like the concept but want something more affordable, the OHI-2 collection starts at USD 2,250 (no date, accuracy at +/- 12 seconds per day). For more information or to place an order, please visit the SNGLRTY website.

2 responses

  1. @200F It really is a cool concept and very creative, and fun to wear.

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