A professional who inspects and tests watch and clock subassemblies and completed watch movements for mechanical and visual defects and makes adjustments to correct defects, using watchmaker's tools and loupe. Responsibilities include:

• Inspects banking of pallet, lock, drop, and slide of escapement.
• Verifies that hairspring is level and centered, and inspects and adjusts beat.
• Tests endshake (vertical play of wheels), using tweezers, to verify that shake is within acceptable limits.
• Examines spring to verify centering between regulator pins and centers regulator lever.
• Examines movement for scratches, and blows out dust or dirt, using airhose.
• Activates watch and clock movements and compares time indicated with master clock to verify accuracy of movements.
• Listens to movements in operation to detect excessive noise.
• Turns time and alarm shafts and pulls alarm buttons to test alarm mechanisms for freedom of movement.
• Examines external surfaces for defects, such as cracked or scratched cases or crystals, loose or misaligned hands, and faulty printing on dials.
• Oils or inspects oiling of pallet stones and jeweled bearings.
• Disassembles movement to point of error and replaces defective parts, using watchmaker's tools.
• Observes minute parts with aid of loupe.
• May clean parts with soft leather and polish case with chamois.