Selector and rotary switches are dials that rotate to control connected machines, motors, or industrial systems. These multi-position switches, support multiple circuits or functions and have labels or marks that identify their set position. Selector-switch assemblies with contact blocks are ready to install in control panels or enclosures. Selector-switch operators without contact blocks require compatible contact blocks to complete the assembly. Hazardous-location selector switches are for environments where flammable gases, liquids, particles, and other combustible materials are present. Selector-switch knobs and replacement parts increase functionalities, replace worn and damaged components, or build new switches. Key switches turn circuits on and off with keys. Potentiometers adjust a circuit's voltage to provide smooth current variation. Cam selector switches toggle between multiple circuits, functions, modes, or electrical states. Rotary selector switches control various circuits or functions.