The automatic COSC-Accredited PF441 chronometer motion that this Parmigiani common operates on offers a 55-hour electrical power reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and may be admired from the sapphire crystal caseback. And admire it you'll, because it shows a lot of https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/