The automated COSC-Qualified PF441 chronometer movement that this Parmigiani vintage operates on provides a 55-hour electrical power reserve, owing to its oscillating mass, and that is in delicately engraved gold, and may be admired in the sapphire crystal caseback. And admire it you'll, since it shows a few of the https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/