The automatic COSC-Qualified PF441 chronometer movement that this Parmigiani common operates on provides a 55-hour power reserve, owing to its oscillating mass, that is in delicately engraved gold, and might be admired through the sapphire crystal caseback. And admire it you may, since it shows several of the greatest decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/