Seiko Cal. 6638 - 901

The 6638-901 is a sought-after Spring Drive piece from Seiko's golden era. It features a Navy dial protected by a Acrylic crystal and offers 190m of water resistance. [seikata-wm-5e6ed744b97f]

Also known as: Bullhead, Golden Tuna

Specifications

Movement

Spring Drive

Case Material

Titanium

Case Width

42mm

Case Thickness

15.5mm

Lug Width

22mm

Crystal

Acrylic

Bezel

Rotating

Water Resistance

190m

Dial Color

Navy

Jewels

26j

Frequency

36,000 bph

Power Reserve

63 hours

Year

1967

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