Seiko Cal. 6640 - 956

This Hand-Winding model from 1995 features a 36mm Gold-Plated case. It features a Blue Sunburst dial protected by a Sapphire crystal and offers 160m of water resistance. [seikata-wm-273a1efa518c]

Also known as: Sumo

Specifications

Movement

Hand-Winding

Case Material

Gold-Plated

Case Width

36mm

Case Thickness

11.2mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

160m

Dial Color

Blue Sunburst

Jewels

25j

Frequency

28,800 bph

Power Reserve

53 hours

Year

1995

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