Seiko Cal. 6637 - 231

The 6637-231 is a sought-after Quartz piece from Seiko's golden era. Powered by the 6637 caliber with 33j jewels beating at 36,000 bph, it delivers a 70 hours power reserve. [seikata-wm-4bc958935b6f]

Also known as: Bullhead

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

43mm

Case Thickness

12.9mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

120m

Dial Color

Cream

Jewels

33j

Frequency

36,000 bph

Power Reserve

70 hours

Year

1998

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