{"product_id":"otsuka-lotec-no-7-5-jumping-hour-automatic-watch-jiro","title":"Otsuka Lotec No.7.5 Jumping Hour Automatic Watch by Jiro Katayama, Disc Display, 40 mm, Unused Full Set","description":"\u003cdiv class=\"jp-product\" data-world=\"Timepieces \u0026amp; Fine Jewelry\"\u003e\n\u003cp class=\"jp-lede\"\u003eJiro Katayama's No.7.5 abandons the conventional dial for an instrument panel of three mechanical ports: a jumping hour aperture, a rotating minute disc and a seconds disc magnified by a sapphire fisheye lens. This example is new and unused, with box, documents, strap and tags.\u003c\/p\u003e\n\u003ch2\u003eThe Piece\u003c\/h2\u003e\n\u003cp\u003eDesigned in Tokyo by Jiro Katayama, the Otsuka Lotec No.7.5 is one of the most visually distinctive mechanical watches of Japan's modern independent movement. Time is read through a three-window interface rather than hands: the hour numeral jumps instantly at the start of each hour, a rotating disc replaces the minute hand, and a small seconds disc keeps the dial in constant motion. The arrangement evokes the analog gauges of laboratory equipment and aviation instruments, a miniature mechanical console rather than a classical watch face.\u003c\/p\u003e\n\u003cp\u003eThe seconds display sits beneath a sapphire fisheye lens whose optical distortion adds depth and curiosity. Mechanically the watch pairs the Miyota 82S5 automatic, a durable and serviceable Japanese caliber, with Otsuka Lotec's own jumping hour module, which converts conventional hour and minute motion into the disc-based display while keeping dependable reliability.\u003c\/p\u003e\n\u003cp\u003eThe 316L stainless steel case carries the same industrial philosophy, finished with hairline brushing and sandblasting instead of mirror polish for a utilitarian, tool-instrument appearance. Katayama began building watch cases and mechanical displays in his small workshop around 2008; early prototypes evolved into the numbered system used today, and the brand gained international recognition when the No.6 won the GPHG Challenge Watch Prize.\u003c\/p\u003e\n\u003cp\u003eThe No.7.5 belongs to the modern catalog era, in which Katayama refined modular mechanical displays built on industrial design principles, and it is one of the clearest expressions of that philosophy. Production volumes are extremely limited, which draws independent-watch enthusiasts, mechanical-display collectors, industrial-design enthusiasts and specialists in Japanese horology.\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, Tokyo)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e No.7.5\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLine\/Series:\u003c\/strong\u003e Otsuka Lotec numbered model series (No.5 \/ No.6 \/ No.7.5 \/ No.8 \/ No.9)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOrigin:\u003c\/strong\u003e Japan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e 316L stainless steel; hairline brushed and sandblasted industrial finish\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e Diameter 40 mm · Thickness 11.2 mm (max 14.8 mm) · Lug width 20 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMovement:\u003c\/strong\u003e Miyota 82S5 automatic base with proprietary Otsuka Lotec jumping hour module; 24 jewels; 21,600 vibrations\/hour; power reserve approx. 40 hours\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFunctions:\u003c\/strong\u003e Jumping hour, minute disc, seconds disc\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCrystal:\u003c\/strong\u003e Sapphire with anti-reflective coating; sapphire fisheye lens for disc magnification\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCaseback:\u003c\/strong\u003e Exhibition sapphire caseback\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWater Resistance:\u003c\/strong\u003e Daily-life resistant\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStrap:\u003c\/strong\u003e Calf leather\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded:\u003c\/strong\u003e Box, documents, strap and tags\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eCondition\u003c\/h2\u003e\n\u003cp class=\"jp-grade\"\u003e\u003cstrong\u003eJaponista grade S\u003c\/strong\u003e · Unworn or as new, complete with original packaging.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eNew and unused condition, observed in hand.\u003c\/li\u003e\n\u003cli\u003eFull set with box, documents, strap and tags.\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\u003eComplete with the maker's box, documents and tags; base caliber Miyota 82S5 with Otsuka Lotec's proprietary jumping hour module. 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=\"\/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=\"\/pages\/japonista-layaway-privilege-program\"\u003eLayaway Privilege™\u003c\/a\u003e.\u003c\/p\u003e\n\u003cp\u003eContinue browsing: \u003ca href=\"\/collections\/collectible-watches\"\u003eCollectible Watches\u003c\/a\u003e\u003c\/p\u003e\n\u003cp class=\"jp-related\"\u003eRelated pieces: \u003ca href=\"\/products\/otsuka-lotec-no6-retrograde-watch\"\u003eOtsuka Lotec No.6 retrograde watch\u003c\/a\u003e · \u003ca href=\"\/products\/otsuka-lotec-no5-kai-jump-hour-watch-full-set\"\u003eOtsuka Lotec No.5 Kai jump hour watch\u003c\/a\u003e · \u003ca href=\"\/products\/lv-tambour-pm-sakura-q1k09-pink-diamond-watch\"\u003eLouis Vuitton Tambour PM Sakura Q1K09 watch\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=\"\/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.7.5 · otsuka lotec jumping hour · jiro katayama no 7.5 · japanese independent jumping hour watch · otsuka lotec miyota 82s5 · otsuka lotec unused full set\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Otsuka Lotec","offers":[{"title":"Default Title","offer_id":52072625701157,"sku":null,"price":10850.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0758\/8829\/6229\/files\/OTSUKALOTECNo7.5JumpingHourWatchJapaneseIndependentHorologyJiroKatayamaDiscDisplayWatch_1.jpg?v=1773382547","url":"https:\/\/japonista.com\/products\/otsuka-lotec-no-7-5-jumping-hour-automatic-watch-jiro","provider":"Japonista","version":"1.0","type":"link"}