The automated COSC-Qualified PF441 chronometer movement that this Parmigiani basic runs on offers a fifty five-hour power reserve, owing to its oscillating mass, that is in delicately engraved gold, and can be admired through the sapphire crystal caseback. And admire it you are going to, since it shows a number https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/