Prospex Diver. Designed for those who treat life as the ultimate adventure, the Seiko Prospex line follows every challenge with technological excellence and style. A modern reimagining of Seiko's 1968 Diver's watch, this handsomely rugged design features a stainless steel case and bracelet with super hard coating, and a tri-fold push button release clasp with secure lock and extender. Framed by a black one way rotating elapsed timing bezel, the black dial includes a date calendar and LumiBrite hands and markers, and is protected by a sapphire crystal with anti-reflective coating on the inner surface. The 23-jewel automatic movement beats at a frequency of 21,600 vibrations per hour, with a power reserve of approximately 50 hours, and can be wound manually or automatically. With secure screwdown crown and caseback, this high-intensity timepiece follows ISO standards for scuba diving. 200m Water Resistant.