Seiko Cal. 6631 - 325

The Seiko 6631-325 represents an important milestone in Seiko's 1979 lineup. The Inner Rotating bezel and 36mm case give it a distinctive presence on the wrist. [seikata-wm-70049a2d1405]

Also known as: Tuna

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

36mm

Case Thickness

9.2mm

Lug Width

21mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

60m

Dial Color

White

Jewels

25j

Frequency

21,600 bph

Power Reserve

49 hours

Year

1979

Related Models

• Seiko 3860-192
• Seiko 6613-947
• Seiko 6274-983
• Seiko 7058-736
• Seiko 4568-118
• Seiko 6262-724
• Seiko 3870-774
• Seiko 5296-702
• Seiko 7195-981
• Seiko 7147-307
• Seiko 5233-949
• Seiko 6249-331