The automated COSC-certified PF441 chronometer movement that this Parmigiani basic operates on provides a fifty five-hour power reserve, owing to its oscillating mass, that's in delicately engraved gold, and can be admired from the sapphire crystal caseback. And admire it you may, since it shows several of the finest decoration https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/