Seiko Cal. 6644 - 998

This Spring Drive model from 1975 features a 41mm PVD Black case. Powered by the 6644 caliber with 36j jewels beating at 28,800 bph, it delivers a 51 hours power reserve. [seikata-wm-bdeab3706d55]

Also known as: Monster

Specifications

Movement

Spring Drive

Case Material

PVD Black

Case Width

41mm

Case Thickness

13.0mm

Lug Width

19mm

Crystal

Mineral

Bezel

Bidirectional

Water Resistance

140m

Dial Color

Silver

Jewels

36j

Frequency

28,800 bph

Power Reserve

51 hours

Year

1975

Related Models

• Seiko 6162-685
• Seiko 0795-572
• Seiko 5213-368
• Seiko 4531-776
• Seiko 6624-367
• Seiko 7160-857
• Seiko 5245-910
• Seiko 7133-767
• Seiko 6682-284
• Seiko 5631-610
• Seiko 6254-445
• Seiko 3827-884