The automatic COSC-Accredited PF441 chronometer motion that this Parmigiani vintage operates on offers a 55-hour energy reserve, owing to its oscillating mass, that's in delicately engraved gold, and might be admired from the sapphire crystal caseback. And admire it you will, because it shows a number of the finest decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/