First Class Double Rotor Skeleton Abraham-Louis Perrelet invented the automatic movement in 1777. Almost two centuries later, in 1995, the brand that bears his name created the calibre Double P-181 rotor. In it, the oscillating mass (first rotor) is located below the movement, while the second rotor rests on the dial where one can admire the automatic winding movement in all its glory. The pink-gold piece with automatic mechanical movement that you see here celebrates the 20th anniversary of that mechanism. Limited to 77 pieces.