Seiko Cal. 6639 - 661

The Seiko 6639-661 represents an important milestone in Seiko's 1972 lineup. The Coin-Edge bezel and 35mm case give it a distinctive presence on the wrist. [seikata-wm-8a9dd1cf3b4f]

Also known as: Sumo

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

35mm

Case Thickness

10.6mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Coin-Edge

Water Resistance

60m

Dial Color

Silver

Jewels

19j

Frequency

28,800 bph

Power Reserve

63 hours

Year

1972

Related Models

• Seiko 6289-920
• Seiko 5638-993
• Seiko 7093-882
• Seiko 5635-768
• Seiko 3858-333
• Seiko 4581-145
• Seiko 0768-416
• Seiko 4455-265
• Seiko 4574-770
• Seiko 0787-916
• Seiko 5214-491
• Seiko 7157-617