The automatic COSC-Licensed PF441 chronometer motion that this Parmigiani typical operates on offers a 55-hour electric power reserve, owing to its oscillating mass, which is in delicately engraved gold, and will be admired through the sapphire crystal caseback. And admire it you may, as it shows several of the finest https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/