Seiko Cal. 6638 - 865

The 6638-865 is a sought-after Solar piece from Seiko's golden era. Powered by the 6638 caliber with 33j jewels beating at 28,800 bph, it delivers a 36 hours power reserve. [seikata-wm-00ad2bb11b2c]

Also known as: Sumo, Bellmatic

Specifications

Movement

Solar

Case Material

Two-Tone

Case Width

41mm

Case Thickness

11.7mm

Lug Width

20mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

150m

Dial Color

Burgundy

Jewels

33j

Frequency

28,800 bph

Power Reserve

36 hours

Year

1994

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