The Longines Master Collection Chronograph Moonphase L2.773.4.71.2 combines timeless elegance with refined mechanical engineering. Its 42 mm stainless steel case houses the L687 automatic movement with a monocrystalline silicon balance-spring and a 66-hour power reserve. The opaline ivory dial features applied Roman numerals, blued steel hands, chronograph counters, discreet date and a moon phase display. A sapphire crystal with anti-reflective coating enhances clarity, while the transparent case back reveals the intricate movement. Finished with a blue alligator strap and triple-safety clasp, it exemplifies classic Swiss watchmaking.