The automatic COSC-Qualified PF441 chronometer motion that this Parmigiani vintage operates on provides a 55-hour electricity reserve, owing to its oscillating mass, that is in delicately engraved gold, and can be admired in the sapphire crystal caseback. And admire it you can, because it shows several of the finest decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/