Seiko Cal. 6637 - 603

The 6637-603 is a sought-after Spring Drive piece from Seiko's golden era. Powered by the 6637 caliber with 23j jewels beating at 21,600 bph, it delivers a 62 hours power reserve. [seikata-wm-25fe65a6b89b]

Also known as: Sumo, Crown

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

38mm

Case Thickness

8.7mm

Lug Width

19mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

40m

Dial Color

Blue Sunburst

Jewels

23j

Frequency

21,600 bph

Power Reserve

62 hours

Year

1984

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