Prospex Automatic Diver. Designed for those who treat life as the ultimate adventure, Seiko Prospex challenges every limit with timepieces created to exceed expectations, engineered with superior style and innovative technology for the sea, sky or land. Inspired by one of Seiko's most iconic diving styles, the case retains the straight contour of the original design with a sharpness enhanced by a sleeker more compact profile. For reliable timing in rough waters, the 23-jewel automatic movement beats at a frequency of 21,600 vibrations per hour, with a power reserve of approximately 41 hours, and can be wound manually or automatically. Framed by a coordinating uni-directional rotating elapsed timing bezel, the vibrant blue dial features a date calendar and LumiBrite hands and markers.