The automated COSC-Qualified PF441 chronometer movement that this Parmigiani traditional runs on offers a fifty five-hour energy reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and might be admired from the sapphire crystal caseback. And admire it you are going to, since it shows https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/