Tudor Black Bay One 31

Tudor's Black Bay One 31, reference M79600-0005, has a 31mm steel case with a polished and satin finish. The case measures 9.5mm thick, with a lug width of 17mm. A flat sapphire crystal covers the blue dial, which is set with diamonds and shows luminous hands and indices. Inside is the manufacture calibre MT5201, a self-winding chronometer movement certified by COSC with a power reserve of about 50 hours. A screw-down crown with the Tudor rose in relief protects the movement. The case is fitted to a steel bracelet with a folding clasp and safety catch. That clasp closes on a case built to withstand depths of 100 metres.