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Some specifications for this reference are on file; the record is incomplete.

Seiko · Vintage

Chronograph 6138

Ref. 6138-0030 — “Bullhead

discontinuedTop-pusher 'Bullhead' casePartially documentedLast reviewed Not yet reviewed

Missing informationCore fields not yet documented for this reference: Case diameter, Water resistance

Bezel insert

Reproduction bezel inlays are widespread

Medium

What to inspect

The coloured bezel inlay is fragile, frequently damaged, and reproduced in volume. Colour match to the dial, print sharpness of the tachymeter scale and the seating of the inlay in the bezel are the checks. A replacement inlay is a common and usually disclosed repair; it becomes an authentication concern only when combined with other substituted parts, or when a listing presents a re-inlaid watch as untouched.

Dial

Colourway mixing between the two variants

Medium

What to inspect

Brown dials appear in black-bezel cases and the reverse, produced by combining two incomplete watches. Neither part is counterfeit; the watch as presented did not leave the factory that way. Check that dial, bezel inlay and subdial tone form one of the two documented combinations.

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