Seiko Cal. 6331 - 991

The Seiko 6331-991 represents an important milestone in Seiko's 1978 lineup. The Coin-Edge bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-dc8b3fe08c2f]

Also known as: Panda, Emperor

Specifications

Movement

Hand-Winding

Case Material

Stainless Steel

Case Width

37mm

Case Thickness

14.7mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

30m

Dial Color

Silver

Jewels

19j

Frequency

28,800 bph

Power Reserve

49 hours

Year

1978

Related Models

• Seiko 7099-635
• Seiko 6189-752
• Seiko 0790-704
• Seiko 7033-321
• Seiko 6649-357
• Seiko 5237-910
• Seiko 7139-385
• Seiko 7127-275
• Seiko 6331-742
• Seiko 7075-686
• Seiko 0755-184
• Seiko 5256-874