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

Seiko · Vintage

Chronograph 6138

Ref. 6138-0011 — “UFO

discontinuedLugless 'Yachtsman' casePartially documentedLast reviewed Not yet reviewed

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

Overview

Nickname
UFO
Production
1970–1979
Era
Lugless 'Yachtsman' case
Status
discontinued

Case

Case material
Stainless steel
Construction
Lugless round case with an integrated bracelet mount, giving the appearance of no lugs at all
Bezel
Internal rotating bezel
Crystal
Hardlex
Crown
Crown at 4; chronograph pushers at 2 and 4

Dial & Hands

Dial
Blue, green or grey 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