Seiko Cal. 6640 - 991

Seiko 6640-991

This Hand-Winding model from 1982 features a 37mm Titanium case. The Coin-Edge bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-7a86f298785e]

Also known as: Sumo

Specifications

Movement
Hand-Winding
Case Material
Titanium
Case Width
37mm
Case Thickness
13.8mm
Lug Width
18mm
Crystal
Mineral
Bezel
Coin-Edge
Water Resistance
70m
Dial Color
Cream
Jewels
35j
Frequency
28,800 bph
Power Reserve
39 hours
Year
1982

Related Models

seikata-wm-7a86f298785e