Seiko Cal. 4437 - 646

The 4437-646 is a sought-after Hand-Winding piece from Seiko's golden era. Powered by the 4437 caliber with 29j jewels beating at 36,000 bph, it delivers a 60 hours power reserve. [seikata-wm-8508c3b97950]

Also known as: Baby Tuna

Specifications

Movement

Hand-Winding

Case Material

Two-Tone

Case Width

34mm

Case Thickness

14.2mm

Lug Width

22mm

Crystal

Sapphire

Bezel

Inner Rotating

Water Resistance

40m

Dial Color

White

Jewels

29j

Frequency

36,000 bph

Power Reserve

60 hours

Year

1975

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