Introduction
Founded by industrial designer Jiro Katayama, Otsuka Lotec has developed one of the most distinctive visual languages in contemporary independent watchmaking. Rather than taking traditional horology as his starting point, Katayama draws from machinery, instrumentation and industrial design, resulting in watches whose displays often resemble gauges or control panels more than conventional dials. Following creations including the double-retrograde No. 6, camera-inspired No. 7.5 and satellite-hour No. 5 Kai, the No. 8 continues this highly mechanical approach.
Introduced in 2026, the No. 8 combines jumping hours with an unusually theatrical retrograde minute display. The hour is shown on a rotating disc to the left, while the minutes progress vertically along the right side before returning to zero through a controlled reset mechanism incorporating a visible flywheel. Beneath the display is a 62-component proprietary module driven by a Miyota 90S5 automatic calibre. Produced in small numbers and available exclusively in Japan through a raffle system, the No. 8 is another fascinating example of Katayama treating the mechanics themselves as an integral part of the watch's design.
Loupe This Scorecard
Grade
M 9.5
Status
Vetted & Approved
Included
Box and papers
Est. value range
$4,000 – $6,000
The Details
Brand
Otsuka Lotec
Dimensions
31mm × 47.8mm × 10.8mm
Model
No. 8
Movement
Automatic Miyota cal. 90S5 with proprietary display module
Reference
No. 8
Bracelet
Black rubber strap
Year
2026
Condition
Like new
Material
Stainless steel
Included
Box and papers
Dial Color
Silver
THE DIAL
More mechanical control panel than conventional dial, the No. 8 divides its display into two distinct zones. Jumping hours are indicated by a rotating disc on the left, while the retrograde minutes travel vertically on the right before making a controlled return to zero. A rotating seconds indicator above the hour display and exposed flywheel further emphasise the watch's industrial character.
THE CONSTRUCTION
The rectangular 316L stainless steel case measures 31mm wide and 47.8mm lug-to-lug, with straight-grained surfaces intentionally retaining an almost machined appearance. A curved sapphire crystal provides additional space over the exposed mechanism, while the crown is positioned at four o'clock and the broad 24mm rubber strap integrates closely with the case.
TIMING MACHINE READOUT
This reading was taken (crown down) with a ONEOF Accuracy Boutique Edition timing machine at time of cataloging. It is provided as a courtesy only, and shall not be construed as a warranty or guarantee of any kind. Please refer to our terms and conditions of sale for more information.
Condition
Watch is in overall like-new condition. The case shows only light signs of wear or handling. Comes with box and papers.
Our Perspective
The No. 8 distils many of the ideas that have made Otsuka Lotec such an intriguing independent watchmaker into one particularly coherent design. Its jumping hours, slowly resetting retrograde minutes and deliberately industrial construction turn the simple act of displaying time into mechanical theatre. Combined with extremely restricted Japan-only availability, it is exactly the sort of unconventional watch that has helped establish Jiro Katayama as one of the most distinctive voices in contemporary Japanese watchmaking.
Eric Ku
Co-founder
