Seiko Cal. 6636 - 740

This Quartz model from 1978 features a 40mm Hardlex-Coated Steel case. Powered by the 6636 caliber with 33j jewels beating at 36,000 bph, it delivers a 63 hours power reserve. [seikata-wm-728d66c4ab50]

Also known as: Tuna

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

13.7mm

Lug Width

19mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

160m

Dial Color

White

Jewels

33j

Frequency

36,000 bph

Power Reserve

63 hours

Year

1978

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