Seiko Cal. 6637 - 840

Seiko 6637-840

The 6637-840 is a sought-after Automatic piece from Seiko's golden era. With its 19mm lug width and 13.3mm profile, it sits comfortably on most wrists. [seikata-wm-73562cccb09c]

Also known as: Monster

Specifications

Movement
Automatic
Case Material
Hardlex-Coated Steel
Case Width
43mm
Case Thickness
13.3mm
Lug Width
19mm
Crystal
Sapphire
Bezel
Fixed
Water Resistance
100m
Dial Color
Navy
Jewels
21j
Frequency
21,600 bph
Power Reserve
43 hours
Year
1989

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