c. 1970–c. 19773 variants
Seiko automatic day-date chronograph commonly called Kakume for its square registers. Documented 6138-0030 examples include 5 Sports Speed-Timer, Speed-Timer and dial printing, with luminous arrow or non-luminous . Dial codes and caseback numbers identify different components; matching parts requires specimen-specific evidence.
Years estimated from 25 dated marketplace listings (5th–95th percentile); seller-stated, unverified.
Production years have not been recorded for these variants.
The dial carries 5 Sports Speed-Timer printing, dark square registers and luminous arrow-shaped hour and minute hands. Its photographed back reads 6138-0030 with a visible 4N serial prefix, although the dealer table says 6NXXXX. The dealer describes the present taupe colour and yellowed minute track as aging, not a separate factory colourway.
Speed-Timer printing without 5 Sports, non-luminous baton hands and red chronograph hands distinguish this photographed dial. The minute track has faded to yellow-beige, and the formerly black tachymeter is anthracite-grey. The dealer notes dial spots and paint loss on the register hands, especially at twelve.
Blue sunburst dial with Chronograph Automatic printing, white square registers, luminous arrow hands and a blue tachymeter. The detailed dealer description and photographs establish blue despite Black in its short specification table. The supplied Seiko fishbone bracelet is described with Z039 end pieces.
Specs shared by all variants. Variant pages show where a variant differs.