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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

Overview

Nickname
Bullhead
Production
1971–1978
Era
Top-pusher 'Bullhead' case
Status
discontinued

Case

Case material
Stainless steel
Construction
Asymmetric case with the crown and both chronograph pushers on the upper flank, giving the 'bull horns' silhouette
Bezel
Fixed outer bezel with tachymeter
Crystal
Hardlex
Crown
Crown and pushers at the top of the case

Dial & Hands

Dial
Reddish-brown or black depending on variant
Lume
Tritium

Movement

Movement
Automatic chronograph
Caliber
6138B
Manufacturer
Seiko
Winding
automatic
Frequency
21,600 vph
Complications
Chronograph (30-minute and 12-hour totalisers), day-date