The automatic COSC-certified PF441 chronometer motion that this Parmigiani common runs on offers a 55-hour electricity reserve, owing to its oscillating mass, which can be in delicately engraved gold, and might be admired throughout the sapphire crystal caseback. And admire it you'll, since it displays many of the greatest decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/