Seiko Cal. 6638 - 387

The 6638-387 is a sought-after Spring Drive piece from Seiko's golden era. It features a Champagne dial protected by a Sapphire crystal and offers 40m of water resistance. [seikata-wm-3b4c2b2bf179]

Also known as: Baby Tuna

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

46mm

Case Thickness

13.8mm

Lug Width

21mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Champagne

Jewels

18j

Frequency

21,600 bph

Power Reserve

47 hours

Year

1976

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