Seiko Cal. 4540 - 637

This Spring Drive model from 1994 features a 42mm Stainless Steel case. Powered by the 4540 caliber with 33j jewels beating at 21,600 bph, it delivers a 58 hours power reserve. [seikata-wm-2f83393d29e5]

Also known as: Sumo

Specifications

Movement

Spring Drive

Case Material

Stainless Steel

Case Width

42mm

Case Thickness

12.1mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

130m

Dial Color

Green

Jewels

33j

Frequency

21,600 bph

Power Reserve

58 hours

Year

1994

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