Seiko Cal. 6631 - 435

The Seiko 6631-435 represents an important milestone in Seiko's 1977 lineup. Powered by the 6631 caliber with 21j jewels beating at 36,000 bph, it delivers a 36 hours power reserve. [seikata-wm-1a04dd03ce59]

Also known as: UFO, World Timer

Specifications

Movement

Kinetic

Case Material

PVD Black

Case Width

40mm

Case Thickness

9.5mm

Lug Width

21mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

140m

Dial Color

Champagne

Jewels

21j

Frequency

36,000 bph

Power Reserve

36 hours

Year

1977

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