Seiko Cal. 5631 - 647

The Seiko 5631-647 represents an important milestone in Seiko's 1968 lineup. The Fixed bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-1a79fce54b32]

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

37mm

Case Thickness

10.7mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

150m

Dial Color

Champagne

Jewels

22j

Frequency

36,000 bph

Power Reserve

40 hours

Year

1968

Related Models

• Seiko 6654-478
• Seiko 6687-371
• Seiko 5293-613
• Seiko 4525-742
• Seiko 6169-229
• Seiko 4472-798
• Seiko 5626-236
• Seiko 3825-346
• Seiko 6328-121
• Seiko 7158-858
• Seiko 6366-965
• Seiko 4518-337