OMEGA Speedmaster Chronoscope

Omega's Speedmaster Chronoscope, reference 329.30.43.51.02.001, is a chronograph with a 43 mm steel case. It measures 12.8 mm thick with a lug-to-lug span of 48.6 mm, and the silver dial sits under a sapphire crystal treated with anti-reflective coating on both sides. Inside is the manual-winding calibre 9908, a column-wheel chronograph with co-axial escapement and a silicon balance spring, certified as a Master Chronometer and resistant to magnetic fields up to 15,000 gauss. Two barrels mounted in series give the movement a 60 hour power reserve. The dial adds small seconds, hour and minute counters, and a tachymeter scale. A display back shows the movement, and the steel bracelet closes with a foldover clasp. Water resistance is rated to 50 metres.