The automatic COSC-Accredited PF441 chronometer movement that this Parmigiani basic runs on provides a fifty five-hour electrical power reserve, owing to its oscillating mass, which can be in delicately engraved gold, and can be admired from the sapphire crystal caseback. And admire it you might, as it displays several of https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/