Seiko Cal. 6638 - 931

The Seiko 6638-931 represents an important milestone in Seiko's 1965 lineup. It features a Burgundy dial protected by a Sapphire crystal and offers 90m of water resistance. [seikata-wm-7437e78c390c]

Specifications

Movement

Solar

Case Material

Titanium

Case Width

44mm

Case Thickness

10.1mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

90m

Dial Color

Burgundy

Jewels

33j

Frequency

36,000 bph

Power Reserve

67 hours

Year

1965

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