Seiko Cal. 3821 - 637

The Seiko 3821-637 represents an important milestone in Seiko's 1966 lineup. Powered by the 3821 caliber with 20j jewels beating at 28,800 bph, it delivers a 64 hours power reserve. [seikata-wm-c72a07f6707d]

Also known as: Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

14.9mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

90m

Dial Color

Green

Jewels

20j

Frequency

28,800 bph

Power Reserve

64 hours

Year

1966

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