Seiko Cal. 6331 - 665

This Spring Drive model from 1970 features a 44mm Hardlex-Coated Steel case. The Bidirectional bezel and 44mm case give it a distinctive presence on the wrist. [seikata-wm-9c11c33c6a75]

Also known as: Bellmatic

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

15.7mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

160m

Dial Color

Black

Jewels

26j

Frequency

21,600 bph

Power Reserve

65 hours

Year

1970

Related Models

• Seiko 0723-522
• Seiko 0711-105
• Seiko 0728-285
• Seiko 4598-397
• Seiko 4473-770
• Seiko 6658-693
• Seiko 0797-716
• Seiko 5676-517
• Seiko 5265-632
• Seiko 4562-834
• Seiko 0746-822
• Seiko 3823-293