Seiko’s Sport Diver series – such as the 1969 Seiko 6119-8021 "NKK" automatic dive watch here, on a vintage stainless-steel Seiko-signed beads-of-rice bracelet – were popular and quite reminiscent of the late 1960’s and 1970’s chic.  
 
But why call this Seiko, an "NKK?"
 
Founded in 1912 and headquartered in Tokyo, NKK Corporation (日本鋼管株式会社, Nippon Kōkan Kabushiki-gaisha) was a major Japanese industrial company and one of the country’s largest steelmakers.
 
NKK made products using the steel from Japan’s first steel mills, and the company’s innovative seamless steel pipe proved superior to conventional welded pipe.  NKK eventually began producing raw steel from iron ore, and would expand greatly in the decades after World War II, with large steelmaking complexes at Fukuyama (in Hiroshima prefecture) and at Kawasaki and Yokohama (the Keihin Steel Works, near Tokyo).
 
In the late 1970s the company expanded its Keihin complex by building an ultramodern steelworks on man-made Ōgi Island in Tokyo Bay.
 
NKK was the second largest steelmaker in Japan (after Nippon Steel Corporation), and in addition to producing a great array of finished and semifinished steel products, the company designed and built industrial plants, ships, and other large-scale steel structures, as well as specialty metals, ceramics, plastics, and chemicals.  Finally, it made computer hardware and software.
 
In early 2000, Japan’s third largest steel manufacturer Kawasaki Steel (川崎製鉄株式会社, Kawasaki Seitetsu Kabushiki-gaisha) and NKK agreed to study cooperation in transportation, maintenance and procurement at their four domestic steelworks, with the aim of enhancing operational efficiencies by leveraging the geographical advantages of adjacent steelworks. 
 
By 2002, the two companies decided to merge and together formed JFE Holdings Inc ( ホールディングス株式会社, Jeiefuī Hōrudingusu Kabushiki-gaisha), and the company’s main business remains steel production.
 
Now the world’s five largest steel maker with revenue in excess of $30 billion annually and with more than 60,000 employees, JFE engages in engineering, ship building, real-estate redevelopment, and LSi business.  The company also operates several overseas subsidiaries, including California Steel Industries in the United States, Fujian Sino-Japan Metal in China, and Minas da Serra Geral in Brazil.
 
The 6119 series, just like its 6106 forefather, were 70 meter diver watches made by Seiko.  The watch company designed the line to address the market for “light” water sports that had gained in widespread popularity during the late 1960’s and 1970’s – hence the 70-meter dive rating; however, these dive watches did not feature diving bezels.  Also of note, the atypical colorways of the day and date wheels, which Seiko did on purpose to allow the wearer to more easily discern the two from one another at a casual glance.
 
Seiko made literally hundreds of Sports diver and Seiko 5 variations during this time period, with the Japanese manufactures’ Suwa and Dani factory seemingly in competition with one another to see which could devise the most compelling models.
 
This steel-grey 6119 diver comes on a vintage stainless-steel bracelet, and with nylon strap, rugged plastic travel case, and spring bar tool.
 
Find an original Seiko Expo '70 advertisement available in the shop here, and read more about Seiko's participation in Expo '70 in one of the vintage Seiko sales campaign books we've added to the site, here.