The automated COSC-Accredited PF441 chronometer movement that this Parmigiani classic operates on offers a 55-hour electricity reserve, owing to its oscillating mass, that's in delicately engraved gold, and might be admired through the sapphire crystal caseback. And admire it you will, as it shows some of the very best decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/