Seiko Cal. 6637 - 591

The Seiko 6637-591 represents an important milestone in Seiko's 1973 lineup. Powered by the 6637 caliber with 21j jewels beating at 36,000 bph, it delivers a 44 hours power reserve. [seikata-wm-ea9353ac7a83]

Also known as: Sea Horse

Specifications

Movement

Kinetic

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

11.4mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

180m

Dial Color

Silver

Jewels

21j

Frequency

36,000 bph

Power Reserve

44 hours

Year

1973

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