Seiko × Hanae Mori Reversible Ref. 2N20-0070 - Dual-Faced, October 1987
When you flip the case of this watch, it is not just the dial color that changes; the very basis of the design shifts as well. On the white side, twelve black Roman numerals framing the time sit directly on the dial, whereas on the dark side, the numerals vanish entirely, with only the XII, III, VI, and IX migrating to the gold-toned bezel. The Seiko × Hanae Mori Ref. 2N20-0070 effectively wears like two distinct watches on a single strap.
**IMPORTANT NOTE: As this item ships from within the European Union, you will not be liable for customs duties within the EU.**
The round case rotates 180 degrees between two horizontal bars that connect to the strap. One side features a white dial, slender black hands, large Roman numerals, and a polished bezel accented by four visible screws. The other side presents a dark anthracite-black surface devoid of indices featuring radial facets that emerge as light catches them. Slender gold hands stand almost alone against this backdrop, while four Roman numerals on the wide gold-toned bezel completely transform how the time is read. The only shared signature between the two sides is the small HM monogram positioned at 6 o'clock.
The distinction extends to the interior of the case as well. This is not a simple dual-sided construction where a single movement drives both faces; instead, each dial possesses its own Seiko Calibre 2N20A quartz movement and dedicated crown. This allows the time on each side to be set independently. The ultra-thin 2N20A movement—measuring approximately 1.5 mm in height is the key technical solution that allows two distinct mechanisms to be housed within a single rotating case. Here, quartz technology serves not merely to ensure precision but to grant true creative freedom in the design.
The "HM" signature belongs to Japanese fashion designer Hanae Mori. The design language Mori established bridging East and West, the classic and the modern is clearly articulated through the watch's two distinct faces. While the white side functions like a traditional dress watch featuring Roman numerals, the black side renders time within an almost abstract graphic composition. The face revealed when the case is flipped is not simply the back of the other; it is a fully functional second watch waiting to be displayed.
The reference number SEIKO / 2N20-0070 and the unique serial number 701381 are engraved on the connecting lugs. The serial code indicates an October production date; when cross-referenced with the 2N20 family's production timeline and verified examples, this specific watch dates to October 1987. Measurements shown in the photograph indicate a case size of approximately 30 mm (excluding the crowns).
The gold-tone case and rotating lug system show light signs of wear consistent with the watch's age, while both dials remain in excellent condition. The black, crocodile-patterned leather strap complements both of the watch's faces. It also comes with the period-correct Seiko presentation box shown in the photographs.
Final Thoughts
The true brilliance of this Hanae Mori timepiece lies not merely in its rotating case, but in how it transforms into a completely different design with each flip. On the white face, time is read via classic Roman numerals on the dial, whereas on the dark face, the numerals are shifted to the bezel, leaving the dial itself almost entirely uncluttered. Thanks to two independent 2N20A movements, these two views are not merely the decorated front and back of the same watch; they become two distinct watch personalities worn on a single wrist.
The product shown was manufactured in 1987.
IT HAS UNDERGONE A COMPLETE PROFESSIONAL OVERHAUL.
The movement was fully disassembled; every component was cleaned, lubricated, and precisely adjusted to ensure flawless operation. (It will not require further servicing for three years, provided it is not exposed to adverse conditions.)
Product Condition: Tested; all functions are fully operational.
