{"product_id":"case-685-tudor-black-bay-58-gmt-ref-m7939g1a0nru-0001","title":"Case #685 — Tudor Black Bay 58 GMT “Coke” Ref. M7939G1A0NRU-0001","description":"\u003cp data-pm-slice=\"1 1 []\"\u003e\u003cstrong\u003eCase #685 — Tudor Black Bay 58 GMT “Coke”\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eRef. M7939G1A0NRU-0001\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eStatus: Available\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCondition: Excellent Pre-Owned\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eScope: Box, Papers, and Cards\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eCase Notes\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe Black Bay 58 GMT takes Tudor’s travel-watch formula and puts it into the proportions collectors had been asking for.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAt 39 mm wide and just 12.8 mm thick, it is dramatically more compact than the original Black Bay GMT while retaining full GMT functionality. The defining feature is the bidirectional 24-hour bezel with its black-and-burgundy anodized aluminum insert, quickly earning the watch its enthusiast nickname: “Coke.”\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAgainst the domed black dial, gilt-tone applied markers and hands preserve the warm vintage character of the Black Bay family. The red GMT hand ties directly into the burgundy half of the bezel and allows home time to remain visible while traveling.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eInside is Tudor’s Manufacture Calibre MT5450-U, an integrated GMT movement certified by both COSC and METAS as a Master Chronometer. It provides approximately 65 hours of power reserve and uses a true jumping local-hour hand for easy time-zone changes.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThis example dates from 2025 and presents in Excellent Pre-Owned condition. It includes its Box, Papers, and Cards and is currently sized for approximately a 7¾-inch wrist.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAs a 2025 example, it retains substantial coverage under Tudor’s five-year transferable guarantee, subject to the exact warranty-card date and Tudor terms.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe Evidence\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eReference: M7939G1A0NRU-0001\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eModel: Black Bay 58 GMT\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eYear: 2025\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCase: Stainless Steel, Polished and Satin Finished\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCase Diameter: 39 mm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCase Thickness: 12.8 mm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eLug Width: 20 mm\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eDial: Domed Black with Gilt Applied Hour Markers\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCrystal: Domed Sapphire\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eBezel: Bidirectional 24-Hour Stainless-Steel Bezel with Black and Burgundy Anodized Aluminum Insert\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCrown: Screw-Down with Tudor Rose\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eMovement: Tudor Manufacture Calibre MT5450-U\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eMovement Type: Automatic Integrated GMT\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCertification: COSC and METAS Master Chronometer\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eFrequency: 28,800 VPH\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eJewels: 34\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003ePower Reserve: Approximately 65 Hours\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eFunctions: Hours, Minutes, Central Seconds, GMT, Date, Jumping Local Hour\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eWater Resistance: 200 meters \/ 660 feet\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eBracelet: Three-Link Rivet-Style Stainless Steel\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eClasp: Tudor T-fit\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eBracelet Fit: Approximately 7¾-inch Wrist\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eCondition: Excellent Pre-Owned\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eFactory Warranty: Remaining Tudor Five-Year Transferable Guarantee, Subject to Exact Card Date\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eIncluded: Box, Papers, and Cards\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eCollector Provenance\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe Black Bay 58 GMT matters largely because Tudor solved one of the biggest objections to its earlier GMT: size.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe original Black Bay GMT delivered genuine travel-watch functionality but did so in the thicker full-size Black Bay architecture. The 58 GMT brought the complication into a 39 mm case while still using an integrated manufacture GMT movement.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThat required more than simply shrinking the watch.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe MT5450-U was engineered around the compact case and retains a true independently adjustable local-hour hand, date synchronization, 65-hour reserve, and Master Chronometer certification.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe black-and-burgundy bezel gives the reference a visual identity of its own and has naturally picked up the familiar collector nickname “Coke.”\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eDesign Provenance\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe watch remains unmistakably part of the Black Bay family.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe domed black dial, gilt-tone details, Snowflake hour hand, aluminum bezel, and rivet-style bracelet all draw on Tudor’s vintage-inspired design vocabulary.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe GMT elements add color without making the dial feel busy.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe burgundy lower half of the bezel gives the watch warmth, while the red GMT hand provides a functional accent against the otherwise black-and-gilt dial.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAt 39 mm and 12.8 mm thick, the proportions remain compact enough for daily use and considerably more restrained than many mechanical GMT watches.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eTechnical Provenance\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe MT5450-U is one of Tudor’s most advanced compact movements.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eIt is certified by both COSC and METAS and provides approximately 65 hours of power reserve.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe local hour hand can be advanced or reversed independently in one-hour increments, with the date synchronized to that adjustment.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThat makes it a true travel GMT: local time can be changed after landing without stopping the watch or disturbing home time.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eMETAS Master Chronometer certification also covers precision, power reserve, water resistance, and resistance to magnetic fields up to 15,000 gauss.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eFrom the Case File\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThis is one of Tudor’s most complete modern sports-watch packages.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe 39 mm case keeps the watch wearable, while the true GMT architecture, rotating 24-hour bezel, date, 200-meter water resistance, and T-fit clasp give it genuine everyday utility.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eCase 685 dates from 2025 and presents in Excellent Pre-Owned condition.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eIt includes its Box, Papers, and Cards and is currently sized for approximately a 7¾-inch wrist.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eBuy with Confidence\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eBST guarantees the authenticity of every watch we sell and provides a 30-day mechanical performance guarantee under normal use.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eAccuracy may vary with age and service history, and water resistance is not guaranteed unless specifically stated and pressure-tested.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eBST Verdict\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe GMT many Tudor collectors were waiting for.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eThe 39 mm case, black-and-burgundy “Coke” bezel, true jumping local-hour GMT, T-fit bracelet, 65-hour reserve, and dual COSC\/METAS certification make the Black Bay 58 GMT one of Tudor’s strongest current sports watches.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eCase 685 adds a 2025 date, Excellent condition, complete BPC presentation, and substantial remaining factory warranty to an already highly versatile reference.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eEvery case deserves a closer look.\u003c\/span\u003e\u003c\/p\u003e","brand":"Baker Street Timepieces","offers":[{"title":"Default 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