The automated COSC-certified PF441 chronometer motion that this Parmigiani basic runs on offers a 55-hour energy reserve, owing to its oscillating mass, which happens to be in delicately engraved gold, and can be admired throughout the sapphire crystal caseback. And admire it you might, since it displays several of the https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/