Seiko Cal. 5661 - 727

The 5661-727 is a sought-after Solar piece from Seiko's golden era. Powered by the 5661 caliber with 23j jewels beating at 36,000 bph, it delivers a 48 hours power reserve. [seikata-wm-42a729204881]

Also known as: Monster, Helmet

Specifications

Movement

Solar

Case Material

PVD Black

Case Width

44mm

Case Thickness

10.1mm

Lug Width

20mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

90m

Dial Color

Navy

Jewels

23j

Frequency

36,000 bph

Power Reserve

48 hours

Year

1984

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