Seiko Cal. 6638 - 813

The Seiko 6638-813 represents an important milestone in Seiko's 1975 lineup. It features a Navy dial protected by a Acrylic crystal and offers 100m of water resistance. [seikata-wm-b83bab6ad7ab]

Also known as: Turtle, Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

44mm

Case Thickness

11.1mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

100m

Dial Color

Navy

Jewels

31j

Frequency

28,800 bph

Power Reserve

55 hours

Year

1975

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