Seiko Cal. 6657 - 784

This Hand-Winding model from 1968 features a 37mm Two-Tone case. The Fixed bezel and 37mm case give it a distinctive presence on the wrist. [seikata-wm-057c549f264e]

Also known as: Sumo, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

37mm

Case Thickness

11.3mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Fixed

Water Resistance

30m

Dial Color

Champagne

Jewels

34j

Frequency

21,600 bph

Power Reserve

50 hours

Year

1968

Related Models

• Seiko 0720-279
• Seiko 6617-756
• Seiko 4442-457
• Seiko 7060-214
• Seiko 6160-783
• Seiko 3864-112
• Seiko 0787-112
• Seiko 5664-871
• Seiko 4584-951
• Seiko 4418-200
• Seiko 7090-630
• Seiko 6253-301