Seiko Cal. 6638 - 910

The Seiko 6638-910 represents an important milestone in Seiko's 1966 lineup. Powered by the 6638 caliber with 28j jewels beating at 21,600 bph, it delivers a 51 hours power reserve. [seikata-wm-ff5e892df217]

Also known as: Sumo, Panda

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

34mm

Case Thickness

12.0mm

Lug Width

19mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

40m

Dial Color

Black

Jewels

28j

Frequency

21,600 bph

Power Reserve

51 hours

Year

1966

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