Seiko Cal. 6640 - 437

Seiko 6640-437

This Spring Drive model from 1977 features a 43mm Titanium case. The Rotating bezel and 43mm case give it a distinctive presence on the wrist. [seikata-wm-b1ebcc5f9246]

Also known as: Monster

Specifications

Movement
Spring Drive
Case Material
Titanium
Case Width
43mm
Case Thickness
10.5mm
Lug Width
19mm
Crystal
Hardlex
Bezel
Rotating
Water Resistance
170m
Dial Color
Blue Sunburst
Jewels
30j
Frequency
36,000 bph
Power Reserve
61 hours
Year
1977

Related Models

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