Men's Japanese Timepieces And Luxury Watches One such mannequin, the 6309 (and its and variants), was launched in 1976 because the “third” major divers watch, with manufacturing lasting into the Nineteen Eighties. When Seiko determined to refresh the Seiko 5 line using the traditional case form of the SKX007/009, it opened the door to more creative and stylistic variations. In principle, the SRPD71, with its blue dial and tan arms and indices, coupled with a steel mesh bracelet, suits within the “Suits” fashion of SKX-cased watches. This watch options hacking and hand-winding capabilities that plenty of Seiko fanatics have at all times desired. Moreover, it is outfitted with a 40-hour energy reserve, resulting in an ideal combination of form and function for a watch.