Seiko Cal. 6657 - 688

Released in 1968, the Cal. 6657 with design code 688 was part of Seiko's domestic market collection. It features a Navy dial protected by a Mineral crystal and offers 110m of water resistance. [seikata-wm-428e5bffc5c6]

Also known as: UFO

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

37mm

Case Thickness

13.6mm

Lug Width

22mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

110m

Dial Color

Navy

Jewels

32j

Frequency

21,600 bph

Power Reserve

59 hours

Year

1968

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