Seiko Cal. 6643 - 784

The 6643-784 is a sought-after Spring Drive piece from Seiko's golden era. The Inner Rotating bezel and 41mm case give it a distinctive presence on the wrist. [seikata-wm-0c78da32efea]

Also known as: Helmet

Specifications

Movement

Spring Drive

Case Material

Two-Tone

Case Width

41mm

Case Thickness

8.7mm

Lug Width

22mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

100m

Dial Color

Green

Jewels

34j

Frequency

21,600 bph

Power Reserve

39 hours

Year

1974

Related Models

• Seiko 6389-770
• Seiko 4559-792
• Seiko 5680-137
• Seiko 5693-682
• Seiko 0784-405
• Seiko 7094-663
• Seiko 4537-173
• Seiko 6134-272
• Seiko 7129-520
• Seiko 7162-585
• Seiko 4561-144
• Seiko 4569-698