Omega Speedmaster 38 Co-Axial Chronograph Watch - 38 mm Steel Case - Black Dial - 324.30.38.50.01.00138 mm stainless steel case, bezel which includes a tachymeter scale on a black aluminium ring, scratch resistant sapphire crystal anti reflective treatment on both sides, black dial includes rhodium plated indexes and hands, three subdials and a date window at 6 o'clock, tachymeter scale, Caliber Omega 3330 self winding movement with chronograph, chronometer, date, approximately 52 hours of power reserve, stainless steel bracelet. Water resistant to