The automatic COSC-Accredited PF441 chronometer movement that this Parmigiani typical runs on offers a 55-hour electrical power reserve, owing to its oscillating mass, that's in delicately engraved gold, and may be admired in the sapphire crystal caseback. And admire it you may, as it shows several of the best decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/