Seiko Cal. 5631 - 648

The 5631-648 is a sought-after Quartz piece from Seiko's golden era. Powered by the 5631 caliber with 23j jewels beating at 21,600 bph, it delivers a 63 hours power reserve. [seikata-wm-02e4e9155301]

Also known as: Golden Tuna

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

40mm

Case Thickness

9.2mm

Lug Width

20mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

140m

Dial Color

Champagne

Jewels

23j

Frequency

21,600 bph

Power Reserve

63 hours

Year

1969

Related Models

• Seiko 6191-627
• Seiko 7042-728
• Seiko 7170-783
• Seiko 4591-306
• Seiko 7027-727
• Seiko 3895-184
• Seiko 4592-919
• Seiko 6394-665
• Seiko 7135-831
• Seiko 6351-652
• Seiko 5643-970
• Seiko 6144-123