The automated COSC-Licensed PF441 chronometer motion that this Parmigiani common runs on provides a 55-hour power reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and can be admired throughout the sapphire crystal caseback. And admire it you may, since it shows a few of https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/