{"product_id":"otsuka-lotec-no5-kai-jump-hour-watch-full-set","title":"Reloj mecánico Otsuka Lotec n.º 5 Kai de hora saltante, de Jiro Katayama, arquitectura revisada, juego completo en estado casi nuevo","description":"\u003cdiv class=\"jp-product\" data-world=\"Timepieces \u0026amp; Fine Jewelry\"\u003e\n\u003cp class=\"jp-lede\"\u003eThe No.5 改 is not simply a revision but a mechanical argument, refined and re-articulated. Where the No.6 leans toward retrograde poetry, the No.5 Kai behaves like a laboratory instrument: a jump hour and rotating minute track rise from layered machinery, and this near-mint example is a full set with a warranty dated 2025\/12\/18.\u003c\/p\u003e\n\u003ch2\u003eThe Piece\u003c\/h2\u003e\n\u003cp\u003eJiro Katayama's No.5 Kai, the revised architecture of the No.5, deliberately dismantles the traditional hierarchy of the dial. A central mechanical bridge sits over layered rotating discs, with peripheral minute indexing and a jumping hour display integrated into the mechanical depth. The layout reads like a pressure gauge, a mechanical counter or an industrial readout: time is no longer hands over a face but data emerging from machinery.\u003c\/p\u003e\n\u003cp\u003eSome collectors pause at the Miyota base, yet Otsuka Lotec's work lies elsewhere. The modified base drives a re-engineered jumping hour system and a central disc architecture that exposes the choreography on the dial side, so the release of energy is visible rather than hidden and reading the time becomes an interaction rather than a glance. It is closer to mechanical interface design than to traditional horology.\u003c\/p\u003e\n\u003cp\u003eThe construction follows the same logic: matte steel surfaces, visible functional screws and emphasized structural geometry, with no decorative polish or Geneva striping. The 316L stainless steel case is finished in a blasted and brushed hybrid, and the sapphire crystal is set to give structural depth to the dial mechanics, placing the watch nearer to aerospace instrumentation and precision measuring devices than to conventional luxury.\u003c\/p\u003e\n\u003cp\u003eWithin Japanese independent watchmaking, where Kurono Tokyo stands for elegance and accessibility, Naoya Hida for classical purity and Hajime Asaoka for haute craftsmanship, Otsuka Lotec occupies its own category as the mechanical experimentalist: structural and conceptual rather than classical, decorative or nostalgic. Releases come in extremely limited batches, and the design is instantly recognizable.\u003c\/p\u003e\n\u003ch2\u003eDetails\u003c\/h2\u003e\n\u003cul class=\"jp-details\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaker:\u003c\/strong\u003e Otsuka Lotec (Jiro Katayama)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e No.5 改 (No.5 Kai, revised architecture)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOrigin:\u003c\/strong\u003e Tokyo, Japan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Industrial 316L stainless steel, matte blasted and brushed hybrid finish\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMovement:\u003c\/strong\u003e Modified Miyota base with proprietary jumping hour system\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDisplay:\u003c\/strong\u003e Jump hour and rotating minute track (central disc architecture)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCrystal:\u003c\/strong\u003e Sapphire\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStrap:\u003c\/strong\u003e Black leather; original plus an additional strap\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEdition:\u003c\/strong\u003e Extremely limited batch release\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded:\u003c\/strong\u003e Box, warranty certificate dated 2025\/12\/18, accessories complete\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eCondition\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eNear mint, collector grade.\u003c\/li\u003e\n\u003cli\u003eSupplied as a full set with box, dated warranty certificate and complete accessories, including an additional strap.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eOtsuka Lotec Atelier\u003c\/h2\u003e\n\u003cp\u003eOtsuka Lotec was founded in Tokyo by the designer and engineer Jiro Katayama, who came to watchmaking through industrial design, metalworking and a fascination with mechanical instruments rather than a Swiss apprenticeship. His founding idea was that a wristwatch could be treated as a miniature instrument whose architecture, materials and motion communicate time with the clarity of a scientific tool. Brushed plates, exposed screws, engraved scales, retrograde arcs and layered mechanical structures make the dial read like a laboratory gauge, an aviation instrument or a mechanical dashboard.\u003c\/p\u003e\n\u003cp\u003eModels are identified by number rather than name; the No.5 Kai, No.6, No.7.5, No.8 and No.9 trace the evolution of Katayama's design language. Production is small-scale and atelier-like, often distributed in restricted quantities through lotteries or tightly controlled releases within Japan, and the watches typically combine reliable Japanese mechanical base movements with proprietary display modules of Katayama's design.\u003c\/p\u003e\n\u003ch2\u003eAuthenticity \u0026amp; Care\u003c\/h2\u003e\n\u003cp\u003eAccompanied by the Otsuka Lotec warranty certificate dated 2025\/12\/18, original box and complete accessories. Every piece is examined and documented in Japan before dispatch and is offered with the Japonista authenticity guarantee.\u003c\/p\u003e\n\u003ch2\u003eDelivery from Japan\u003c\/h2\u003e\n\u003cp\u003ePacked by hand in Japan and shipped insured and tracked by EMS or an equivalent express service. Import duties and taxes, where applicable, are payable on arrival. Returns follow our \u003ca href=\"\/es\/policies\/refund-policy\"\u003epublished policy\u003c\/a\u003e.\u003c\/p\u003e\n\u003cdiv class=\"jp-closing\"\u003e\n\u003cp\u003eConsidered offers are welcome through Send an Offer, and each one is reviewed personally. Pieces over $1,000 may be reserved over several payments with \u003ca href=\"\/es\/pages\/japonista-layaway-privilege-program\"\u003eLayaway Privilege™\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003eContinue browsing: \u003ca href=\"\/es\/collections\/collectible-watches\"\u003eCollectible Watches\u003c\/a\u003e\u003c\/p\u003e\n\u003cp class=\"jp-related\"\u003eRelated pieces: \u003ca href=\"\/es\/products\/otsuka-lotec-no6-retrograde-watch\"\u003eOtsuka Lotec No.6 retrograde watch\u003c\/a\u003e · \u003ca href=\"\/es\/products\/otsuka-lotec-no-7-5-jumping-hour-automatic-watch-jiro\"\u003eOtsuka Lotec No.7.5 jumping hour watch\u003c\/a\u003e · \u003ca href=\"\/es\/products\/audemars-piguet-cobra-18k-yellow-gold-bracelet-watch-twelve\"\u003eAudemars Piguet Cobra yellow gold bead-link bracelet\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"jp-cta\" data-world=\"Timepieces \u0026amp; Fine Jewelry\"\u003e\n\u003cp class=\"jp-cta-eyebrow\"\u003eReference Hunting\u003c\/p\u003e\n\u003cp\u003eName the reference number, dial and year, and the Hunting Salon™ watches Japan’s collector market for it, then inspects and documents the piece before it ships insured to you. \u003ca href=\"\/es\/pages\/hunting-salon%E2%84%A2\"\u003eRequest a watch search →\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cp class=\"jp-search\"\u003eCollectors also search: otsuka lotec no.5 kai · otsuka lotec no 5 改 · otsuka lotec jump hour · jiro katayama no.5 · japanese independent jump hour watch · otsuka lotec full set\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Otsuka Lotec","offers":[{"title":"Default Title","offer_id":52174512914725,"sku":null,"price":28980.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0758\/8829\/6229\/files\/OtsukaLotecNo.5KaiJumpHourWatchJapanRareFullSetIndependentJiroKatayama_1.png?v=1775004531","url":"https:\/\/japonista.com\/es\/products\/otsuka-lotec-no5-kai-jump-hour-watch-full-set","provider":"Japonista","version":"1.0","type":"link"}