Kurono Tokyo’s “Structure” Chronograph S1 Is Hajime Asaoka’s Take on the Perfect Tool Watch
A 40mm steel case, enlarged subdials and fluorescent orange hands put function first in the brand’s new STRUCTURE series.
Summary
Hajime Asaoka launches Kurono Tokyo’s STRUCTURE series with the 40mm “Structure” Chronograph S1.
A four-layer dial nearly eliminates parallax between the chronograph hand and indices.
Available in Teal, Salmon, and White, it drops November 19 with a price tag of $3,690 USD.
Kurono Tokyo is launching a new design direction. The “Structure” Chronograph S1 is the first release in the STRUCTURE series, which founder and acclaimed independent watchmaker Hajime Asaoka describes as a new kind of tool watch. Earlier Kurono pieces were built on classical watchmaking proportions with a modern edge, but the S1 puts function first. It packs a full tool-watch chronograph into a 40mm case, slightly larger than the brand’s usual sizing. “My design ethos for this project can be distilled into two words: Functional Elegance,” Asaoka said in the release.
The heart of the watch is its four-layer dial, built to bring each hand as close as possible to the markers it reads against. The result is that the central chronograph hand sits with almost no parallax over the indices, making elapsed-time readings more precise. The subdials are enlarged as far as the layout allows, and their counter hands share the same fluorescent orange as the chronograph hand for quick reading at a glance.
The S1 comes in Teal, Salmon and White, each in a high-polished 316L stainless steel case that is 13.15mm thick including its sapphire box crystal, 50.2mm lug-to-lug, with 22mm lugs and a rubber strap. Inside is the automatic NE86PWT movement, beating at 28,800 vph with 34 jewels and roughly 45 hours of power reserve.
The S1 is priced at $3,690 USD and will be sold exclusively online through Kurono Tokyo’s website starting November 19, 2026, at 11 p.m. JST/ 9 a.m. in New York. The release is limited and won’t be repeated, with deliveries expected from mid-December 2026. From November 12 – 19, the watch is on display at Kurono’s salons in Aoyama, Tokyo, and Shanghai, where visitors can try it on.
