Seiko Prospex Marinemaster 1968 Heritage Diver’s Watch. Ever since its first diver’s watch in 1965, Seiko has developed new technologies, features, and designs that have made its diver’s watches favorites among professional divers and adventurers the world over. In 1968, just three years after Seiko’s first diver’s watch was made, the brand’s engineers raised the bar by creating a high-beat diver’s watch with 300 meters of water resistance, laying one of the foundation stones on which future Seiko diver’s watch development would be based. It featured a high-precision 10-beat automatic movement, a one-piece case construction, a screw-down crown, and a unidirectional rotating bezel. The 1968 watch struck a chord with successive generations of sports watch enthusiasts thanks to its robust design and high functionality. Seiko introduces two new creations that re-interpret the design of 1968 in the Marinemaster collection.