Seiko Cal. 6631 - 645

This Automatic model from 1976 features a 44mm Titanium case. Powered by the 6631 caliber with 30j jewels beating at 36,000 bph, it delivers a 65 hours power reserve. [seikata-wm-f2193cea4921]

Also known as: Baby Tuna

Specifications

Movement

Automatic

Case Material

Titanium

Case Width

44mm

Case Thickness

10.5mm

Lug Width

19mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

170m

Dial Color

Black

Jewels

30j

Frequency

36,000 bph

Power Reserve

65 hours

Year

1976

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