Seiko created Japan's first diver's watch in 1965. This watch inaugurated over five decades of innovation that have made Seiko diver's watches the global standard. This special diver's watch is equipped with a high-grade automatic movement, caliber 8L35, which is hand assembled and adjusted by Seiko's master watchmakers at the Shizukuishi Watch Studio in Morioka. A resilient one piece structure case suitable for saturation diving is hand polished using the Zaratsu technique (creates a distortion free case surface that is mirror like in reflection) which accentuates the edges and brings additional sharpness and beauty to the light. Each of the three hands has a different design, length, and width, and the LumiBrite on each has a distinct shape so that the time is easily read, under any circumstances. The dual curved sapphire crystal delivers exceptional clarity from any viewing angle, as well as enhanced durability. The differentiated 12, 6, and 9 markers ensure that the watch can be read without error even 300 meters down. The contrast of the dial and special, long lasting LumiBrite allow for legibility even in the darkest environment. The one way rotating bezel ensures the absolute safety that divers require.