{"product_id":"seiko-sbge257-grand-seiko-sport-collection-spring-drive-gmt-40mm-stainless-steel-automatic-movement-sapphire-crystal","title":"SEIKO SBGE257 Grand Seiko Sport Collection Spring Drive GMT 40mm Stainless Steel Automatic Movement Sapphire Crystal","description":"```html\n\u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n\u003ctr\u003e\u003ctd colspan=\"2\" style=\"font-weight:800;padding:8px;background:#d9d9d9;\"\u003eProduct Highlights\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd colspan=\"2\" style=\"padding:8px;\"\u003eA new era Spring Drive GMT with a ceramic bezel. This model features the third mechanism \"Spring Drive,\" which uses the mainspring found in mechanical watches as its power source while achieving the same high precision as quartz watches. The second hand of a Spring Drive watch moves smoothly across the dial rather than ticking. The sweeping motion created by this unique mechanism expresses the Japanese aesthetic of \"time flowing and changing.\" To consider more active use, zirconia ceramics have been adopted for the bezel material. Zirconia ceramics possess the highest strength and toughness among fine ceramics and boast excellent processing quality for surface polishing, making it a beautiful material. It has outstanding scratch resistance, allowing the bezel, which is the most prone to scratches while wearing the watch, to maintain its inherent beauty for a long time. The crown at the 4 o'clock position is designed with practicality in mind, ensuring that it does not hinder smooth wrist movement during active activities.\nGrand Seiko\nManufacture\nGrand Seiko is a true manufacture that handles everything in-house, from movement development to design, manufacturing, assembly, adjustment, inspection, and shipping. In an environment where each component can be researched and developed from the material, cutting-edge technology is fused with the highest level of craftsmanship. The \"Grand Seiko Studio Shizukuishi,\" overlooking the majestic Iwate Mountain. The \"Shinshu Time Artisan Workshop,\" surrounded by the mountains and lakes of Shinshu. In these two workshops nurtured by rich nature, three movements are created.\nThe Spirit of Takumi\nThe attitude of Grand Seiko's artisans who endlessly pursue the essence of time. This is akin to the way of \"Do\" seen in traditional Japanese martial arts, tea ceremony, and flower arrangement. By honing their skills and deepening their spirituality, this path becomes sharper and opens up new realms. To embody the ever-changing time within a watch, they strive for high precision, visibility, and the beauty of form. Creating a true ideal watch that shines eternally across generations. The challenge of the artisans knows no end.\nLight and Shadow\nThe Japanese delicately perceive, savor, and cherish the countless expressions created by light and shadow as time flows. The design is characterized by sharp, flat surfaces and straight lines without distortion. The mirror surface is meticulously polished with the exceptional skills of artisans. The multi-faceted cut indices and thick hands. The symbolic designs are created to produce beautiful expressions even as light changes with time and place, shining brilliantly while maintaining high visibility.\nSpecifications\nExterior: Stainless Steel  Bezel: Ceramics\nGlass Material: Dual Curve Sapphire\nCoating: Anti-reflective coating on the inner surface\nLumibrite: Yes (hands and indices)\nCase Size: Width 40.5mm × Thickness 14.7mm\nWrist Size (Maximum): 195mm\nClasp: One-push three-fold type\nDrive System: Spring Drive\nPower Reserve: Approximately 72 hours (about 3 days) at maximum winding\nAccuracy: Average monthly deviation ±15 seconds (equivalent to daily deviation ±1 second)\nWater Resistance: Daily life reinforced water resistance (20 ATM)\nMagnetic Resistance: Yes\nWeight: 172.0 g\nOthers:\n- 24-hour hand (dual time display function)\n- Screw-lock crown\n- Calendar (date) function\n- Number of jewels: 30\n- Second hand stop function\n- Power reserve display function\n- Case back with lion emblem\n- Screw back (due to manufacturing reasons, there may be individual differences in the orientation of the case back)\n- Calendar-linked time difference correction function\nGrand Seiko continues to pursue the essence of watches as a timepiece to walk through life with and evolves.\n■ 9R Spring Drive\nThe Spring Drive is Seiko's unique drive mechanism that uses the mainspring found in mechanical watches as its power source while controlling accuracy with precise signals from the quartz oscillator, which is the control system of quartz watches. The Spring Drive, equipped with a hybrid engine that incorporates the best features of both mechanical and quartz watches, can be described as \"a mechanical watch that achieves high precision\" and also \"a quartz watch that does not use batteries or motors.\"\n◆ A Hybrid Mechanism of Mechanical and Quartz\nThe major elements in the mechanism of how a watch operates are \"power\" and \"control system.\"\n- \"Power\" refers to the force that drives the watch.\n- \"Control system\" refers to the mechanism that controls the movement of the watch.\nThe Spring Drive is a hybrid movement that adopts \"power: high torque\" from mechanical watches and \"control system: high precision through IC control\" from quartz watches.\n\"Power\" is the \"mainspring\" used in mechanical watches.\nThe power of the Spring Drive comes from the \"mainspring\" used in mechanical watches, making it a self-contained drive system that does not rely on batteries or motors. When winding the crown, the mainspring is wound, and the force trying to unwind the mainspring is transmitted to the gears, moving the hands attached to the gears. The reason the Spring Drive can turn the thick and heavy hands characteristic of Grand Seiko is that it utilizes a high-torque mainspring (rather than a motor).\nThe \"control system\" is the \"Tri-Synchro Regulator.\"\nThe control system of the Spring Drive is a unique speed control mechanism that uses the electrical signals from the IC and quartz oscillator found in quartz watches. Imagine a toy powered by a mainspring. If the unwinding speed is not adjusted, the mainspring will unwind all at once, and the toy will stop. Therefore, a mechanism is needed to maintain a constant unwinding speed. The \"Tri-Synchro Regulator,\" developed for the Spring Drive, fulfills this role. The TRI in Tri-Synchro Regulator (TRI【3】-SYNCHRO【synchronize】 REGULATOR【speed control device】) refers to:\n1. Mechanical force\n2. Electrical signal\n3. Magnetic force\nThese three interact to create the precise movement of the second hand.\n1. Mechanical force (power: mainspring)\nElectricity is generated by the unwinding force of the mainspring. For example, a bicycle light uses the force of the rotating tire to emit light. The Spring Drive generates electricity using the same principle, with the rotor and coil wound \"stator\" serving as the generator. The rotor generates a small amount of electrical energy by rotating eight times per second.\n2. Electrical signal (accurate signal: IC and quartz oscillator)\nThe quartz oscillator emits an accurate signal. A small amount of electricity is used to drive the quartz oscillator and IC. When power is transmitted to the quartz oscillator, it sends an accurate signal of 32,768Hz per second to the IC, equivalent to quartz.\n3. Magnetic force (brake: rotor and stator)\nThe rotor is braked to control speed. The IC compares the accurate signal from the quartz oscillator with the rotor's rotation speed, intermittently applying magnetic brakes to prevent the rotor from spinning too fast, maintaining a constant speed. By keeping the rotor's rotation constant, controlled movements are transmitted in the order of rotor, gears, and hands, accurately marking the time.\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\u003ctd colspan=\"2\" style=\"font-weight:800;padding:8px;background:#d9d9d9;\"\u003eSpecifications\u003c\/td\u003e\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eDrive System\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eMechanical\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eRadio Automatic Correction Function\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eNone\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eDisplay Method\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eAnalog\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eCase\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eEdge CE, Body SS, Case Back SS (Full Metal Case)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eGlass\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eDual Curve Sapphire Glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eBand Material\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eMetal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eBand (Adjustable)\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eScrew Type\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eAccuracy\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eAverage monthly deviation ±15 seconds (equivalent to daily deviation ±1 second)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eSpecification 1\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eAutomatic winding (with manual winding) Case back with lion emblem Screw back Screw-lock crown\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eSpecification 2\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003eNumber of jewels: 30 24-hour hand (dual time display function) Power reserve display function Calendar-linked time difference correction function\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border-bottom:1px solid #5d5d5d;font-weight:600;padding:6px 10px;width:35%;\"\u003eList Price\u003c\/td\u003e\n\u003ctd style=\"border-bottom:1px solid #ccc;padding:6px 10px;\"\u003e¥891,000 JPY\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n```","brand":"SEIKO","offers":[{"title":"Default Title","offer_id":47586196652116,"sku":"SBGE257","price":854720.0,"currency_code":"JPY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0284\/7401\/5828\/files\/SBGE257_1.jpg?v=1787850606","url":"https:\/\/www.ippojapanwatch.com\/ja\/products\/seiko-sbge257-grand-seiko-sport-collection-spring-drive-gmt-40mm-stainless-steel-automatic-movement-sapphire-crystal","provider":"IPPO JAPAN WATCH ","version":"1.0","type":"link"}