Seiko Cal. 6645 - 728

The 6645-728 is a sought-after Hand-Winding piece from Seiko's golden era. Powered by the 6645 caliber with 25j jewels beating at 21,600 bph, it delivers a 37 hours power reserve. [seikata-wm-608529ed7d47]

Also known as: Helmet, Rally

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

40mm

Case Thickness

10.2mm

Lug Width

22mm

Crystal

Hardlex

Bezel

Coin-Edge

Water Resistance

80m

Dial Color

Cream

Jewels

25j

Frequency

21,600 bph

Power Reserve

37 hours

Year

1993

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