Omega Planet Ocean 600 M Omega Co-axial Master Chronometer Chronograph Watch - 45.5 mm Titanium Case - Unidirectional Grey Silicon Nitride Ceramic Bezel - Grade 5 Titanium Dial - 215.90.46.51.99.00145. 5 mm titanium case with anti magnetic properties and helium escape valve, transparent back, screw in crown, unidirectional rotating grey silicon nitride ceramic bezel with orange rubber and Liquidmetal diving scale, scratch resistant sapphire crystal, sand blasted grade 5 titanium dial with Arabic numerals and a date window at the 6 oclock position, small seconds sub dial, as well as 60 minute and 12 hour counters on one dial, caliber Omega 9900