Seiko Cal. 6638 - 148

The 6638-148 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 6638 caliber with 31j jewels beating at 21,600 bph, it delivers a 69 hours power reserve. [seikata-wm-55297f42a283]

Also known as: World Timer, Crown

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

39mm

Case Thickness

10.6mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

120m

Dial Color

Champagne

Jewels

31j

Frequency

21,600 bph

Power Reserve

69 hours

Year

1966

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