Seiko Cal. 6640 - 955

Released in 1986, the Cal. 6640 with design code 955 was part of Seiko's domestic market collection. With its 18mm lug width and 10.5mm profile, it sits comfortably on most wrists. [seikata-wm-115aa1309ef0]

Also known as: Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

40mm

Case Thickness

10.5mm

Lug Width

18mm

Crystal

Hardlex

Bezel

Bidirectional

Water Resistance

100m

Dial Color

White

Jewels

31j

Frequency

28,800 bph

Power Reserve

39 hours

Year

1986

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