The automatic COSC-certified PF441 chronometer movement that this Parmigiani classic runs on offers a 55-hour power reserve, owing to its oscillating mass, which is in delicately engraved gold, and may be admired from the sapphire crystal caseback. And admire it you might, since it shows a number of the finest https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/