Seiko Cal. 6640 - 847

The 6640-847 is a sought-after Hand-Winding piece from Seiko's golden era. With its 21mm lug width and 8.3mm profile, it sits comfortably on most wrists. [seikata-wm-a5e876ca3840]

Also known as: Sumo, Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

34mm

Case Thickness

8.3mm

Lug Width

21mm

Crystal

Hardlex

Bezel

Inner Rotating

Water Resistance

80m

Dial Color

Navy

Jewels

36j

Frequency

28,800 bph

Power Reserve

36 hours

Year

1994

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