Seiko Cal. 5631 - 312

The Seiko 5631-312 represents an important milestone in Seiko's 1972 lineup. Powered by the 5631 caliber with 19j jewels beating at 28,800 bph, it delivers a 63 hours power reserve. [seikata-wm-2223bbd9fe49]

Also known as: Rally, Golden Tuna

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

9.8mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

30m

Dial Color

Green

Jewels

19j

Frequency

28,800 bph

Power Reserve

63 hours

Year

1972

Related Models

• Seiko 5628-373
• Seiko 0788-705
• Seiko 6662-614
• Seiko 4563-152
• Seiko 6640-460
• Seiko 6646-310
• Seiko 5237-683
• Seiko 6622-119
• Seiko 3884-616
• Seiko 6653-981
• Seiko 3830-842
• Seiko 5299-529