Seiko Cal. 6631 - 730

Seiko 6631-730

The 6631-730 is a sought-after Hand-Winding piece from Seiko's golden era. The Coin-Edge bezel and 46mm case give it a distinctive presence on the wrist. [seikata-wm-26b42dd737d5]

Also known as: Helmet, Sportsmatic

Specifications

Movement
Hand-Winding
Case Material
Hardlex-Coated Steel
Case Width
46mm
Case Thickness
9.6mm
Lug Width
22mm
Crystal
Sapphire
Bezel
Coin-Edge
Water Resistance
70m
Dial Color
Champagne
Jewels
22j
Frequency
28,800 bph
Power Reserve
53 hours
Year
1990

Related Models

seikata-wm-26b42dd737d5