The automatic COSC-certified PF441 chronometer motion that this Parmigiani vintage runs on offers a fifty five-hour electrical power reserve, owing to its oscillating mass, that's in delicately engraved gold, and can be admired through the sapphire crystal caseback. And admire it you can, as it shows some of the best https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/