Tudor - a Black Bay GMT watch, 41mm., Tudor - a Black Bay GMT wrist watch. Stainless steel case with calibrated bezel. Case width 41mm. Reference 79830, serial Q197492. Automatic movement with quick date set. Black dial with luminous hour markers, date aperture to three. Fitted to an unsigned black and red nylon 'NATO' style strap with stainless steel pin buckle. Box and papers.