Longines Ultra-Chron Classic

The Longines Ultra-Chron Classic, reference L2.937.4.72.2, has a 40 mm round case in steel. The watch is chronometer-certified. Self-winding calibre L836.6 provides up to 52 hours of power reserve and beats at 36,000 vibrations per hour. A scratch-resistant sapphire crystal covers the dial, with several layers of anti-reflective coating on both sides. The sunray silver dial has applied indexes and polished silvered hands. A black alligator leather strap with a calf leather underside closes with a pin buckle. The dial includes a date display and central seconds. The case measures 10.95 mm thick and 47.2 mm lug-to-lug, with water resistance rated to 50 metres.