Pre-owned Tudor Black Bay 58 GMT ref. M7939G1A0NRU-0001 (2024) features the MT5450-U caliber, which carries both COSC and METAS certification, covering everything from accuracy to magnetic resistance, water resistance, and overall performance. The case sticks with the familiar 39mm Black Bay 58 proportions, though at 12.8mm thick, it wears noticeably slimmer than most GMT models. Tudor also adjusted the crown slightly, letting it sit a bit lower and closer to the case. The bezel embraces that classic black and red “Coke” look, an homage to vintage travel watches, while the rest stays true to Tudor’s design language. The gilt dial, Snowflake hands, and overall layout keep it grounded in the brand’s heritage. Shop Tudor Black Bay Collection