The automatic COSC-Licensed PF441 chronometer movement that this Parmigiani basic operates on provides a 55-hour power reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and can be admired from the sapphire crystal caseback. And admire it you can, since it displays some of the https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/