The Omega Speedmaster Professional Platinum 321: case, 42mm, platinum and gold alloy (PT950, AU20) with sapphire crystal and caseback, based on the case used for reference ST 105.012, the first watch worn on the Moon. Ceramic, dot-over-90 bezel with white enamel numerals; white gold indexes and hands, coated with Super LumiNova; onyx “stepped” dial with meteorite sub-dials (meteorite of lunar origin). Movement, Omega caliber 321, 27mm x 6.74mm, lateral clutch, column-wheel controlled, with overcoil balance spring; 2.5 Hz/18,000 vph, with 44 hour power reserve; plates and bridges plated with Sedna gold. Limited production, as total annual 321 movement production is expected to be around 2000 movements, but not a limited edition.