Seiko Cal. 6623 - 637

The Seiko 6623-637 represents an important milestone in Seiko's 1980 lineup. The Inner Rotating bezel and 44mm case give it a distinctive presence on the wrist. [seikata-wm-414383aa66ff]

Also known as: Tuna, Sportsmatic

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

44mm

Case Thickness

8.2mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

110m

Dial Color

Silver

Jewels

28j

Frequency

36,000 bph

Power Reserve

52 hours

Year

1980

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