Use heavy machinery to extract coal out of the ground.
Performs any combination of following duties to insert clock and watch assemblies in cases: Inserts and secures crown and stem into clock and watch movements, using loupe, tweezers, screwdriver, and other jeweler’s tools. Cleans case, using airhose, and inserts movement into case. Presses revolving plastic cup against crown or rubs crown against plastic strip to wind movement. Sets watch to specified time prior to testing. Secures watertight cases, using pliers, or places assembly in device that tightens case automatically. May remove temporary crown and stem prior to assembly, using handtools. May measure stem, using gauge, and file stem to specified length. May screw crowns onto stems. May test waterproof watches in air pressure and water tanks.