Seiko Cal. 6631 - 729

The 6631-729 is a sought-after Kinetic piece from Seiko's golden era. Powered by the 6631 caliber with 29j jewels beating at 21,600 bph, it delivers a 69 hours power reserve. [seikata-wm-42acedf07c65]

Also known as: Sumo

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

10.8mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

160m

Dial Color

White

Jewels

29j

Frequency

21,600 bph

Power Reserve

69 hours

Year

1974

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