Seiko Cal. 5640 - 421

Seiko 5640-421

This Spring Drive model from 1977 features a 38mm PVD Black case. With its 22mm lug width and 14.3mm profile, it sits comfortably on most wrists. [seikata-wm-3521b2ad63f7]

Also known as: Monster, Sportsmatic

Specifications

Movement
Spring Drive
Case Material
PVD Black
Case Width
38mm
Case Thickness
14.3mm
Lug Width
22mm
Crystal
Sapphire
Bezel
Coin-Edge
Water Resistance
160m
Dial Color
Navy
Jewels
20j
Frequency
28,800 bph
Power Reserve
68 hours
Year
1977

Related Models

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