Seiko Cal. 6637 - 318

The Seiko 6637-318 represents an important milestone in Seiko's 1997 lineup. With its 21mm lug width and 11.3mm profile, it sits comfortably on most wrists. [seikata-wm-cba52c30f323]

Also known as: Sumo

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

40mm

Case Thickness

11.3mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

200m

Dial Color

Burgundy

Jewels

24j

Frequency

28,800 bph

Power Reserve

45 hours

Year

1997

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