Seiko Cal. 5637 - 640

The 5637-640 is a sought-after Hand-Winding piece from Seiko's golden era. It features a Blue Sunburst dial protected by a Acrylic crystal and offers 60m of water resistance. [seikata-wm-78d9418f1989]

Also known as: Helmet

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

38mm

Case Thickness

14.2mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

60m

Dial Color

Blue Sunburst

Jewels

36j

Frequency

36,000 bph

Power Reserve

48 hours

Year

1989

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