Seiko Cal. 6637 - 900

This Spring Drive model from 1974 features a 35mm Gold-Plated case. Powered by the 6637 caliber with 19j jewels beating at 36,000 bph, it delivers a 40 hours power reserve. [seikata-wm-75d512ea0490]

Also known as: Bullhead

Specifications

Movement

Spring Drive

Case Material

Gold-Plated

Case Width

35mm

Case Thickness

11.1mm

Lug Width

22mm

Crystal

Mineral

Bezel

Fixed

Water Resistance

120m

Dial Color

Silver

Jewels

19j

Frequency

36,000 bph

Power Reserve

40 hours

Year

1974

Related Models

• Seiko 6143-282
• Seiko 6678-421
• Seiko 7137-126
• Seiko 3835-926
• Seiko 5260-811
• Seiko 6386-495
• Seiko 7092-281
• Seiko 5275-587
• Seiko 0769-483
• Seiko 3859-149
• Seiko 6383-118
• Seiko 0744-408