Zenith 3019PHC-5121, Screw for balance cock and barrel bridge

• ZENITH original screw, not in factory packaging.
• Fits ZENITH cal:
• 3019 PHC, 3019PHF, 400Z, 405Z, 410Z, 420Z, 4001, 4002, 4009, 4021, 4026
• Fits ROLEX cal: 4030

Versions:

• 3019PHC: date.
• 3019PHF: H:= 7.55 mm, day, date, month, moon phase.
• 400*: H:= 6.50 mm, date, redesign.
• 405*: H:= 6.50 mm, fly back function.
• 410*: H:= 7.55 mm, day, date, month, moon phase.
• 420*: H:= 5.70 mm, manual wind.
• 4001: H:= 7.77 mm, day, date, month, moon phase.
• 4002: H:= 6.50 mm, date.
• 4009: H:= 7.55 mm, day, date, month, moon phase, fly back.
• 4021: H:= 6.50 mm, 60 s, 30 min counter, sceletonized at escapement, power reserve display.
• 4026: H:= 9.35 mm, rattrapante, big date.

• * = suffix Z: redesigned fourth wheel and escape wheel.