

1967_Seiko_JDM_Catalog_No.2, page 24
The 6217-8000/8001, universally known as the 62MAS (from the 62 base caliber plus autoMAtic Selfdater), was Seiko's first professional dive watch, launched July 1965 with 150m water resistance, a 37mm case without crown guards, drilled lugs, and an external rotating bezel. Designed under Taro Tanaka with Tatsuro Akabane, it was reportedly rushed to serve the Japanese Antarctic Research Expedition, running the 17-jewel caliber 6217A (18,000 bph). Collectors prize the first-series "small crown" 6217-8000 (produced only ~April–May 1965); it appeared in the 1977 film The Deep.