The automatic COSC-certified PF441 chronometer motion that this Parmigiani typical runs on offers a 55-hour energy reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and may be admired from the sapphire crystal caseback. And admire it you might, as it displays a lot of https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/