The Speed timer is a product line of Seiko’s automatic chronographs from the 1970's. Speedtimer branded watches - 6138/6139 - were mechanically the same as their regular counterparts, but had small stylistic differences that set them apart from the general production of the same watch. They were built in far lesser numbers and offered in fewer markets than their normally aspirated variants. As such Speedtimer are highly priced amongst collectors. It is important to note that not all Seiko chrono

The King Seiko Vanac was manufactured between 1972 and 1974 only, in a number of variations, but all sporting colorful dials, facetted crystals and angular cases. Both Seiko production plants contributed, Suwa with the standard KS 5626 caliber and Daini with the 5246 and 5256 calibers that exist in some normal KS but are most common as Vanacs. 
A Vanac is basically/exceptionally a KS with added extras, faceted glass, a gold bezel, a high quality bracelet (no folded metal links here) drilled lug

When quartz was well established, at the end of the Seventies, the Seiko 1978 JDM catalogue showed the twin quartz caliber for the first time, however there were (eventually) at least three different design technologies behind the Seiko twin quartz models.
[color=black][size=medium][font=Times]While quartz based watches are extremely accurate compared to mechanical watches th

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When quartz was well established, at the end of the Seventies, the Seiko 1978 JDM catalogue showed the twin quartz caliber for the first time, however there were (eventually) at least three different design technologies behind the Seiko twin quartz models.
[color=black][size=medium][font=Times]While quartz based watches are extremely accurate compared to mechanical watches th