The automatic COSC-certified PF441 chronometer movement that this Parmigiani traditional operates on offers a 55-hour electric power reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and might be admired through the sapphire crystal caseback. And admire it you can, as it shows many of https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/