Seiko Cal. 6381 - 645

Released in 1970, the Cal. 6381 with design code 645 was part of Seiko's domestic market collection. The Coin-Edge bezel and 42mm case give it a distinctive presence on the wrist. [seikata-wm-4ab9bbf1404b]

Also known as: Sumo, Tuna

Specifications

Movement

Hand-Winding

Case Material

PVD Black

Case Width

42mm

Case Thickness

9.8mm

Lug Width

20mm

Crystal

Acrylic

Bezel

Coin-Edge

Water Resistance

140m

Dial Color

Silver

Jewels

20j

Frequency

36,000 bph

Power Reserve

37 hours

Year

1970

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