Seiko Cal. 5637 - 331

Released in 1978, the Cal. 5637 with design code 331 was part of Seiko's domestic market collection. It features a Black dial protected by a Mineral crystal and offers 30m of water resistance. [seikata-wm-bbcd1ce3a789]

Also known as: Golden Tuna

Specifications

Movement

Automatic

Case Material

PVD Black

Case Width

42mm

Case Thickness

12.8mm

Lug Width

20mm

Crystal

Mineral

Bezel

Inner Rotating

Water Resistance

30m

Dial Color

Black

Jewels

32j

Frequency

21,600 bph

Power Reserve

46 hours

Year

1978

Related Models

• Seiko 6238-238
• Seiko 6154-632
• Seiko 6645-609
• Seiko 4473-948
• Seiko 6320-601
• Seiko 6252-692
• Seiko 7193-997
• Seiko 7042-733
• Seiko 7059-162
• Seiko 6255-936
• Seiko 0734-998
• Seiko 7153-246