My collection of Seiko mechanical chronographs. Twelve of them, all restored and working well. Some of the bracelets are non original but all else is authentic. They were produced from 1969 until 1979. Two movement types are represented here; the 3 register, 2 sub dial 6138 and the more basic 2 register 6139 with only one sub dial’.
There is dispute about who produced the first automatic (self wind) chronograph, but of the three contenders I think it was the Seiko that hit the market first in 1969 and blitzed the others in the marketplace.