Seiko Cal. 6638 - 442

The 6638-442 is a sought-after Quartz piece from Seiko's golden era. Powered by the 6638 caliber with 30j jewels beating at 36,000 bph, it delivers a 60 hours power reserve. [seikata-wm-7c54cc3ac37b]

Also known as: Bellmatic

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

34mm

Case Thickness

14.9mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

200m

Dial Color

Cream

Jewels

30j

Frequency

36,000 bph

Power Reserve

60 hours

Year

1987

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