A professional who inspects assembled watch winding and setting mechanisms for mechanical and surface defects, using tweezers and loupe. Responsibilities include:

• Moves stem in and out to verify clicking into winding and setting positions and turns stem in each position to test for ease of winding and setting.
• Moves barrel of mechanism to test for amount of vertical play (endshake), using tweezers, and determining from experience whether shake is within acceptable limits.
• Examines movement for scratches and presence of dirt, using loupe.