Cutting then profiles the cogs, wheels and pinions using a milling cutter which removes unwanted material until the perfect profile is obtained. Jaeger-LeCoultre’s exceptional quality is due to a series of processes developed and perfected over the firm’s long history. These include rolling the pinions and the balance-wheel staff in order to improve the working of the watch. It is a manual operation which demands great skill, exceptional dexterity and excellent eyesight. An extremely delicate task given the tiny dimensions and the minuscule space worked on.