The Omega Speedmaster Professional Moonwatch 311.30.42.30.01.001 is the definitive modern iteration of the legendary chronograph that earned its “Moonwatch” title by becoming the first watch worn on the lunar surface. This 42mm stainless steel icon stays true to its historic roots with the signature black step dial featuring applied Omega logo and luminous hour markers, paired with the classic dot-over-90 bezel configuration that enthusiasts cherish. The manual-winding Caliber 1861 continues the legacy of the original movement that passed NASA’s rigorous testing, offering the same column-wheel chronograph mechanism and 48-hour power reserve that proved reliable in space. The hesalite crystal maintains authentic vintage appeal with its distinctive warm glow and slight distortion, while the anodized aluminum tachymeter bezel shows the perfect matte black finish. Designed for professional use, this Speedmaster features the asymmetrical case with protected crown and pushers, along with Super-LumiNova coated hands for optimal readability in any conditions. The stainless steel bracelet with flat links and push-button clasp offers period-correct styling, completing the classic Moonwatch aesthetic. Every detail meets NASA’s original specifications, from the moonwatch-professional dial text to the 300m water resistance that far exceeds its space requirements. This reference represents the purest expression of Omega’s most famous watch – the only timepiece certified for extravehicular activity (EVA) and still flight-qualified by NASA today. For collectors and enthusiasts alike, this Speedmaster Professional offers an authentic piece of space history with the same mechanical integrity and design that made it an icon, making it one of the most important chronographs ever created and a cornerstone of any serious watch collection.