The automatic COSC-Accredited PF441 chronometer movement that this Parmigiani traditional runs on provides a 55-hour ability reserve, owing to its oscillating mass, which is in delicately engraved gold, and can be admired with the sapphire crystal caseback. And admire it you will, as it displays a few of the best https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/