Seiko Cal. 6638 - 720

Seiko 6638-720

The 6638-720 is a sought-after Solar piece from Seiko's golden era. Powered by the 6638 caliber with 25j jewels beating at 28,800 bph, it delivers a 65 hours power reserve. [seikata-wm-67458be5d03e]

Also known as: Silverwave

Specifications

Movement
Solar
Case Material
Hardlex-Coated Steel
Case Width
44mm
Case Thickness
14.4mm
Lug Width
22mm
Crystal
Hardlex
Bezel
Coin-Edge
Water Resistance
120m
Dial Color
Green
Jewels
25j
Frequency
28,800 bph
Power Reserve
65 hours
Year
1994

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seikata-wm-67458be5d03e