Caliber CH 28-520 IRM QA 24H

Self-winding Chronograph Caliber

DESCRIPTION

Self-winding Chronograph Caliber.
The new chronograph caliber CH 28-520 IRM QA 24H consists of 456 individual parts.
It is a mechanical movement featuring a column-wheel mechanism with a flyback function, power-reserve indicator, Annual Calendar, and a day/night indication.
It runs at a frequency of 28,800 semi-oscillations per hour (4 Hertz), assuring high rate accuracy and a very constant amplitude of the balance.
The winding power is delivered unidirectionally with a heavy 21K gold rotor.
As all mechanical movements manufactured by Patek Philippe, the new caliber displays the prestigious Geneva Seal, a privilege shared by only the most meticulously crafted movements.

Technical data

  • Annual Calendar Chronograph
  • Chronograph with 60-minute and 12-hour monocounter
  • Annual Calendar mechanism
  • Day, date, month by apertures
  • Annual date correction on March 1
  • Power reserve and day/night display
  • Overall diameter: 33 mm
  • Height: 7.68 mm
  • 40 jewels, 14 bridges
  • Balance: Gyromax
  • Vibrations per hour: 28,800
  • Power reserve: 55 h max.
  • Balance spring: Breguet
  • Number of parts: 456

WATCHES CONTAINING THIS CALIBER:

5960P_001
5960P_001