Longines 12.68Z-301, Regulator for none shock-protection.

• LONGINES original part, NOS without factory packaging.
  

• Fits cal: 12.68Z, 12.68ZS for watches without shock-protection.
  

Versions:

• 12.68Z:     sub second, H=4,25 mm.
• 12.68ZS:    sweep second, H=5,45 mm.
• 12.68Z:     Quantieme, calendar, sub second, H=5,10 mm.
• 12.68Z:     Stopseconde, "chronograph", H=6,10 mm.

Each version with flat or Breguet hairspring, no shock protection, shock resist or incabloc.