Seiko Cal. 6638 - 851

This Spring Drive model from 1999 features a 38mm Hardlex-Coated Steel case. Powered by the 6638 caliber with 35j jewels beating at 28,800 bph, it delivers a 38 hours power reserve. [seikata-wm-691084dbd009]

Also known as: Bullhead, Helmet

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

11.6mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Rotating

Water Resistance

190m

Dial Color

Cream

Jewels

35j

Frequency

28,800 bph

Power Reserve

38 hours

Year

1999

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