Seiko Cal. 6640 - 628

Released in 1986, the Cal. 6640 with design code 628 was part of Seiko's domestic market collection. It features a Navy dial protected by a Mineral crystal and offers 60m of water resistance. [seikata-wm-008ee543dbde]

Specifications

Movement

Quartz

Case Material

Hardlex-Coated Steel

Case Width

45mm

Case Thickness

15.8mm

Lug Width

20mm

Crystal

Mineral

Bezel

Rotating

Water Resistance

60m

Dial Color

Navy

Jewels

17j

Frequency

28,800 bph

Power Reserve

47 hours

Year

1986

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