Seiko Cal. 6640 - 940

The Seiko 6640-940 represents an important milestone in Seiko's 1983 lineup. Powered by the 6640 caliber with 33j jewels beating at 28,800 bph, it delivers a 64 hours power reserve. [seikata-wm-44f52318e778]

Also known as: Tuna

Specifications

Movement

Kinetic

Case Material

Gold-Plated

Case Width

44mm

Case Thickness

9.3mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Inner Rotating

Water Resistance

180m

Dial Color

Navy

Jewels

33j

Frequency

28,800 bph

Power Reserve

64 hours

Year

1983

Related Models

• Seiko 6377-310
• Seiko 6212-679
• Seiko 6355-665
• Seiko 3860-892
• Seiko 4413-454
• Seiko 6149-276
• Seiko 6299-344
• Seiko 4583-270
• Seiko 4439-134
• Seiko 6640-183
• Seiko 0762-783
• Seiko 4514-219