Seiko Cal. 6638 - 436

The 6638-436 is a sought-after Quartz piece from Seiko's golden era. Powered by the 6638 caliber with 21j jewels beating at 36,000 bph, it delivers a 64 hours power reserve. [seikata-wm-bea8c5647b33]

Also known as: UFO, Silverwave

Specifications

Movement

Quartz

Case Material

Titanium

Case Width

35mm

Case Thickness

12.5mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

170m

Dial Color

Champagne

Jewels

21j

Frequency

36,000 bph

Power Reserve

64 hours

Year

1967

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