The automated COSC-Licensed PF441 chronometer motion that this Parmigiani typical operates on provides a 55-hour electric power reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and will be admired in the sapphire crystal caseback. And admire it you are going to, as it shows https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/