Seiko Cal. 6640 - 751

This Quartz model from 1990 features a 35mm PVD Black case. Powered by the 6640 caliber with 18j jewels beating at 21,600 bph, it delivers a 42 hours power reserve. [seikata-wm-014988cb7c66]

Also known as: Sumo, UFO

Specifications

Movement

Quartz

Case Material

PVD Black

Case Width

35mm

Case Thickness

14.2mm

Lug Width

18mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

60m

Dial Color

Champagne

Jewels

18j

Frequency

21,600 bph

Power Reserve

42 hours

Year

1990

Related Models

• Seiko 6670-315
• Seiko 4530-686
• Seiko 0726-896
• Seiko 7044-249
• Seiko 6665-375
• Seiko 5659-805
• Seiko 6681-973
• Seiko 4522-977
• Seiko 4491-198
• Seiko 6681-356
• Seiko 4528-843
• Seiko 0765-604