A professional who inspects and adjusts mainspring barrel assembly, utilizing either of following methods. Responsibilities include:

• (1) Grasps barrel arbor with pliers and locks arbor by means of adjustable ring on plier arms.
• Holds barrel and turns arbor to wind mainspring.
• Allows pliers to hang freely to observe spinning motion as result of spring unwinding, indicating faulty assembly.
• Separates faulty assemblies and places rejected assemblies by type of reject in containers for repair.
• (2) Winds spring to determine if arbor hook is secured in hole of center coil, using hand winding device.
• Tests endshake (vertical play) of barrel, using tweezers.
• Separates faulty barrel assemblies.