Bold, rugged GPS smartwatch is built to U.S. military standard 810 for thermal, shock and water resistance — with a large solar-charged display and durable 50 mm polymer case Solar charging: Power Glass lens extends battery life, producing 50% more energy than the standard Instinct 2 solar watch Infinite battery life in smartwatch mode when exposed to 3 hours of direct sunlight (50,000 lux) per day Built-in LED flashlight with variable intensities and strobe modes gives you greater visibility while you train at night and provides convenient illumination when you need it