The automatic COSC-certified PF441 chronometer motion that this Parmigiani vintage runs on offers a fifty five-hour energy reserve, owing to its oscillating mass, which is in delicately engraved gold, and might be admired in the sapphire crystal caseback. And admire it you will, as it shows several of the finest https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/