The automated COSC-Accredited PF441 chronometer movement that this Parmigiani traditional runs on offers a 55-hour electricity reserve, owing to its oscillating mass, which is in delicately engraved gold, and can be admired with the sapphire crystal caseback. And admire it you might, as it displays several of the very best https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/