Prospex U.S. Special Edition. Designed for those who treat life as the ultimate adventure, Seiko Prospex keeps moving forward, meeting every challenge with technological excellence and winning design. With an intricately patterned brown dial inspired by turtle shells, this exciting Special Edition celebrates Prospex’s official sponsorship of Oceanic Society, America’s first ocean conservation non-profit, and its global work to study and protect the seven species of sea turtles and their ocean habitats. For reliable timing in rough waters, the 24-jewel automatic movement, which beats at a frequency of 21,600 vibrations per hour, provides a power reserve of approximately 41 hours and offers manual winding capability. Framed by a black ceramic uni-directional rotating elapsed timing bezel, the dial features LumiBrite hands and markers, as well as a day/date calendar in both English and Kanji. Crafted of stainless steel, with scratch-resistant anti-reflective sapphire crystal, and secure screwdown crown and Special Edition caseback with sea turtle image, this durable timepiece follows ISO standards for scuba diving at depths of up to 200 meters. Includes additional brown silicone strap. 200 meters (660 feet), follows ISO standards and is suitable for scuba diving.