Seiko Cal. 6639 - 421

The Seiko 6639-421 represents an important milestone in Seiko's 1977 lineup. It features a Silver dial protected by a Mineral crystal and offers 60m of water resistance. [seikata-wm-1cd7ffc36622]

Also known as: Turtle, Navigator

Specifications

Movement

Hand-Winding

Case Material

Titanium

Case Width

41mm

Case Thickness

12.3mm

Lug Width

20mm

Crystal

Mineral

Bezel

Bidirectional

Water Resistance

60m

Dial Color

Silver

Jewels

29j

Frequency

36,000 bph

Power Reserve

62 hours

Year

1977

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