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. Crafted of stainless steel, this high-intensity timepiece follows ISO standards for scuba diving and is equipped with a secure screwdown crown and caseback and a tri-fold push button release clasp with secure lock and extender. 200m Water ResistantTechnology Model: SRPL51 Collection: Prospex Gender: Men's Dial Color: Blue Strap Material: Stainless Steel Strap Detail: Stainless steel bracelet Movement: Automatic Caliber: 4R35 Movement Detail: Caliber 4R3521,600 vibrations per hour23 jewelsPower reserve: approximately 41 hours Case Material: Stainless steel case Case Diameter (mm): 41.7 Case Thickness (mm): 12.3 Case Length (mm): 49.5 Crystal Type: Hardlex crystal Water Resistance: 200 meters (660 feet), follows ISO standards and is suitable for scuba divingFeaturesProspex DiverInspired by one of Seiko’s most iconic diving styles, with the angular design enhanced by a sleeker more compact profileAutomatic with manual winding capabilityBlue dialBlue uni-directional rotating elapsed timing bezelMagnified date calendarLumiBrite hands and markersScrewdown crown and casebackTri-fold push button release clasp with secure lock and extender