Seiko Cal. 6687 - 991

The Seiko 6687-991 represents an important milestone in Seiko's 1981 lineup. The Inner Rotating bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-c878742a7df3]

Also known as: Baby Tuna

Specifications

Movement

Solar

Case Material

Gold-Plated

Case Width

37mm

Case Thickness

14.1mm

Lug Width

20mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

190m

Dial Color

Black

Jewels

22j

Frequency

36,000 bph

Power Reserve

45 hours

Year

1981

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