As a keen observer of the independent side of Japanese watchmaking, I felt honored when Precision Watch Co. reached out on behalf of Jiro Katayama. Katayama-san is a small-scale watchmaker I have been following for a few years. What I find fascinating is his self-taught watchmaking, a quality he shares with Hajime Asaoka that beggars belief.

As only the second Western journalist to get all the details on the latest piece from Jiro Katayama and a chat with him, my story on the Otsuka Lotec No.7.5 inspired me. His watches are still only for sale in Japan, with plans for worldwide export within 2024–25. However, through a close friend, I managed to find one. In our insular watch world, many of us dance to the beat of the same drum. We appreciate a watch that is instantly recognizable, with a dial, indices, and hands indicating the time of day and, often, a large dollop of vintage charm. The Otsuka Lotec No.7.5 has none of these qualities and is all the better for it. You won’t get to go hands-on with this watch at your local GTG, that’s for sure. I’ll try to channel the charming and surprisingly comfortable alien feeling it inspires.

Hands-on with the Otsuka Lotec No.7.5

An oddball with a retro-futuristic finesse

First of all, yes, this Otsuka Lotec No.7.5 is now mine. It’s a keeper, and I feel lucky. Small brands like Jiro Katayama’s Otsuka Lotec do not send us watches on loan for reviews as they mostly struggle to meet demand with small-scale and just-in-time production. Tokyo is also a long way to travel for an atelier visit, though not for lack of wanting to. The No.7.5 on my wrist is one of the 100-180 pieces Katayama-san will produce and assemble this year. This includes new models, and this year, it will happen with the help of Kurono Tokyo watchmakers.

Hands-on with the Otsuka Lotec No.7.5

Through a close friend in Tokyo, I was fortunate to be able to purchase one, and I didn’t hesitate for a nanosecond. Why? I am a big fan of future-haute horology from Urwerk, MB&F, and Vianney Halter, even if I might never have that kind of budget, no matter how much I consolidate. This is another classic case of writing a story and falling for the subject. It happens too often but usually with watches way above my budget. So, let’s put this down to a lot of luck. Many of you know that I am a fan of colors, intricate dial art, and polished details, all of which are absent from this wrist-strapped machine. Calling it a “wristwatch” almost seems to be a disservice.

Hands-on with the Otsuka Lotec No.7.5

An alien on the wrist

I was worried about the 40mm size, and wire lugs make for unpredictable lug-to-lug measurements and ergonomics. Here, though, it all works, starting with the clamshell design of the case. The round shape, paired with the floating potential of the airy wire lugs, is easily balanced by a matte backing leather on the strap. This custom calfskin number is quite stiff initially, but it forms to the wrist, as you can see from the shots. Even with my preference for not-too-tight straps, the No.7.5 stays firmly in place, and it does wear very compactly.

It measures 45mm from lug to lug and 11mm thick, not including the three lens-like displays. At 4mm, the tallest is the fish-eye sapphire hour oculus, and I get the 8mm camera inspiration. But it’s amazing what a big metal nugget with three sapphire displays will do to your perceptions of size. And the best part? The minute display being at about 2 o’clock means you only have to let it slip ever so slightly out from your cuff to check the minutes. And once you’re used to its alien visage, the legibility is great.

Hands-on with the Otsuka Lotec No.7.5

Wearing a watch is a form of roleplay

Does that claim make sense or aggravate you? Perhaps you still adhere to the watch being a time-telling instrument of pure necessity. Many of us buy pilot’s watches that don’t fit under our shirts and brawny 44mm divers for a day at the office. We live vicariously through our wristwear and daydream of piloting a jet, driving a fast car from the ’50s, or diving. That’s all good, and I’m the same. It improves most days at the office, but what daydream adventures does the Otsuka Lotec No.7.5 spark? Well, it is comfortable yet very outlandish, alien even, as if developed in a parallel universe where the idea of dials and hands never made it past the drawing board. Judging by the easy legibility of this steel nugget, I understand how it can be seen as a perfectly natural alternative.

Hands-on with the Otsuka Lotec No.7.5

As to how it makes me feel? Ignoring the 50m water resistance (due to the complex case and displays), it makes me feel like Captain Nemo of the Nautilus, the submarine from Jules Verne’s iconic novel Twenty Thousand Leagues Under the Seas. It looks like a futurist version of a marine chronometer, some of which were regulator-style timepieces. Yes, it might have three sapphire-fitted circular oculus apertures, but it is, by all definitions, a regulator. It has separate discs (instead of sub-dials and hands) for the hours, minutes, and seconds. The big joy comes in watching the small minute pointer edge towards 00 and savoring the soft click as the new hour snaps into place. And despite its industrial monochrome look, the instant-clicking, perfectly centered hour numeral has a deep quality feel. So does the finishing on the case, a smooth shape where you can’t hide any flaws.

An accurate beast

Not many people try on or use a timepiece like this as an everyday wearer. But it deserves to be. The Miyota-based 8-series caliber has been regulated, and though setting time to the second is challenging, it keeps very accurate deviances while being surprisingly easy to read. It makes me wonder, yet again, why the watchmaking industry is so intent on sticking to well-known centuries-old recipes. I mean, look at any other car or useful appliance; if they had the same user interface and functionality as a century ago, would we buy them or even sit in them? Unlike anything you’ve probably felt on the wrist, the Otsuka Lotec No.7.5 is a great and surprisingly legible watch. As the product of the unbound imagination of Katayama-san in his small workshop, it brings enthusiasm without the brand and exclusivity baggage.

Hands-on with the Otsuka Lotec No.7.5


The No.7.5 might not be for everyone, but if you get hooked by its polarizing goggle-eyed looks, you’re done for. Sure, it is not easy to acquire, but it represents sincere value for money and offers a pure difference in a saturated watch market. Many of you might have the same view as me, being slightly fed up with all the retro love without the budget to splurge on something like an Urwerk. Other owners include quirk-master Phil Toledano, aka @misterenthusiast, and small-cased-grail aficionados like The Armoury’s Mark Cho. I’m partial to a polished bevel and a hand-polished Grand Seiko index twinkling in the light. However, this offers a different perspective on horology and an unpolished yet immaculately executed fascination with micro-mechanics. I would even consider a second one. The price is ¥297,000 (roughly €1,875), and for full specs and a chat with its creator, read my launch article here.

Fratelli, how would you feel about wearing a watch without a normal dial? Are you still surfing the retro-tool-watch wave, or are you ready for something different? Let me know in the comments.