Tissot 2400-401, Winding stem

• TISSOT original winding stem.
  

• Thread: 0.90 MM.

• Fits cal: 2400, 2401, 2403, 2404

Versions: 1971 - 1972

• 2400:     base caliber.
• 2401:     modifications.
• 2403:     new regulator.
• 2404:     modified plate.