The automated COSC-Qualified PF441 chronometer movement that this Parmigiani basic runs on offers a 55-hour electricity reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and can be admired with the sapphire crystal caseback. And admire it you may, as it shows some of the https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/