TUDOR Black Bay Fifty-Eight M79010SG-000139 mm silver case, brown leather bracelet Case: 39 mm 925 silver case, satin finished open case back with sapphire crystal Bezel: Unidirectional rotatable bezel in 925 silver with 60 minute graduated disc in matte taupe anodized aluminum and silver gilded markings and numerals Movement: Manufacture Caliber MT5400 (COSC) Self winding mechanical movement with bidirectional rotor system Dial: Taupe, domed Winding Crown: 925 silver screw down winding