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