Seiko Cal. 6688 - 991

The Seiko 6688-991 represents an important milestone in Seiko's 1988 lineup. Powered by the 6688 caliber with 25j jewels beating at 28,800 bph, it delivers a 50 hours power reserve. [seikata-wm-fd3f437858a1]

Also known as: Helmet

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

44mm

Case Thickness

14.6mm

Lug Width

22mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

150m

Dial Color

Burgundy

Jewels

25j

Frequency

28,800 bph

Power Reserve

50 hours

Year

1988

Related Models

• Seiko 0727-422
• Seiko 7188-615
• Seiko 0796-199
• Seiko 0764-350
• Seiko 6119-235
• Seiko 4541-320
• Seiko 4432-214
• Seiko 6125-349
• Seiko 5261-715
• Seiko 5275-933
• Seiko 4575-169
• Seiko 4591-561