This 42 mm model features sapphire crystal glass on both the front and caseback, presented on a polished-brushed stainless steel bracelet. The design draws inspiration from the 4th generation Speedmaster worn on the moon. Its black varnished and lacquered double plate step dial is complemented by white varnished and lacquered subdials set within rhodium-plated frames. Details include the OMEGA logo and indexes, Moonwatch style hands, and the famous dot over 90 on the black ceramic bezel ring. The watch is driven by the OMEGA Co-Axial Master Chronometer Calibre 3861, which powers the small seconds sub-dial, 30-minute recorder and 12-hour recorder, along with the central chronograph function.