Seiko Cal. 6637 - 338

The Seiko 6637-338 represents an important milestone in Seiko's 1976 lineup. The Bidirectional bezel and 34mm case give it a distinctive presence on the wrist. [seikata-wm-47bd7850e542]

Also known as: Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

34mm

Case Thickness

12.7mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

180m

Dial Color

Navy

Jewels

30j

Frequency

28,800 bph

Power Reserve

44 hours

Year

1976

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