The automated COSC-Qualified PF441 chronometer motion that this Parmigiani basic runs on offers a 55-hour energy reserve, owing to its oscillating mass, that's in delicately engraved gold, and can be admired with the sapphire crystal caseback. And admire it you will, as it displays a number of the greatest decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/