Seiko Cal. 6657 - 531

The Seiko 6657-531 represents an important milestone in Seiko's 1978 lineup. Powered by the 6657 caliber with 21j jewels beating at 21,600 bph, it delivers a 47 hours power reserve. [seikata-wm-629d5019ab5f]

Also known as: Sumo

Specifications

Movement

Quartz

Case Material

Two-Tone

Case Width

42mm

Case Thickness

8.1mm

Lug Width

18mm

Crystal

Sapphire

Bezel

Fixed

Water Resistance

180m

Dial Color

Burgundy

Jewels

21j

Frequency

21,600 bph

Power Reserve

47 hours

Year

1978

Related Models

• Seiko 4481-866
• Seiko 0780-759
• Seiko 7092-720
• Seiko 0776-585
• Seiko 6248-747
• Seiko 6151-251
• Seiko 6652-889
• Seiko 4443-405
• Seiko 0748-131
• Seiko 4548-806
• Seiko 0732-357
• Seiko 6310-537