Omega Seamaster Planet Ocean 600 M Omega Co-Axial GMT Watch - 43.5 mm Platinum Case - Black Ceramic Bi-Directional Bezel - Black Dial - Black Leather Strap - 232.98.44.22.01.00143. 5 mm platinum case, transparent back, self locking crown, black ceramic bi directional rotating bezel, sapphire crystal with anti reflective treatment on both sides, black dial set with bi directional 24 hour GMT rotating bezel, caliber 8615 self winding movement with date, approximately 60 hours of power reserve, black leather strap. Water resistant to 600 m (2000 ft).