The automated COSC-Accredited PF441 chronometer motion that this Parmigiani vintage operates on provides a fifty five-hour electrical power reserve, owing to its oscillating mass, which can be in delicately engraved gold, and will be admired through the sapphire crystal caseback. And admire it you might, because it displays a number https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/