Seiko Cal. 5638 - 940

Seiko 5638-940

The Seiko 5638-940 represents an important milestone in Seiko's 1971 lineup. Powered by the 5638 caliber with 35j jewels beating at 28,800 bph, it delivers a 63 hours power reserve. [seikata-wm-9670f1ea29ba]

Also known as: Bullhead, Helmet

Specifications

Movement
Hand-Winding
Case Material
Gold-Plated
Case Width
44mm
Case Thickness
12.6mm
Lug Width
20mm
Crystal
Mineral
Bezel
Rotating
Water Resistance
160m
Dial Color
Blue Sunburst
Jewels
35j
Frequency
28,800 bph
Power Reserve
63 hours
Year
1971

Related Models

seikata-wm-9670f1ea29ba