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