Breguet contributes to the improvement of watchmaking principles, which he was already known for, and develops an abundance of innovations. His first major break-through is the creation of the self-winding watch, or perpetuelle. A short time later, he invents the gong-springs, creates its own aesthetic codes, which include the first engine-turned dials (guilloche), innovates with the terminal curve spring or Breguet balance spring, and launches the one hand subscription watch.