Seiko Cal. 6638 - 527

This Automatic model from 1977 features a 35mm Hardlex-Coated Steel case. It features a Burgundy dial protected by a Mineral crystal and offers 160m of water resistance. [seikata-wm-1f7e0215d5c4]

Also known as: Sumo, Helmet

Specifications

Movement

Automatic

Case Material

Hardlex-Coated Steel

Case Width

35mm

Case Thickness

14.5mm

Lug Width

20mm

Crystal

Mineral

Bezel

Coin-Edge

Water Resistance

160m

Dial Color

Burgundy

Jewels

17j

Frequency

21,600 bph

Power Reserve

61 hours

Year

1977

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