Seiko Cal. 6631 - 218

The Seiko 6631-218 represents an important milestone in Seiko's 1972 lineup. Powered by the 6631 caliber with 31j jewels beating at 36,000 bph, it delivers a 37 hours power reserve. [seikata-wm-6c7b5cbeaefa]

Also known as: Panda, Bellmatic

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

46mm

Case Thickness

14.9mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

70m

Dial Color

White

Jewels

31j

Frequency

36,000 bph

Power Reserve

37 hours

Year

1972

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