contact devices [3]
Examples of components that connect a device to an electric circuit.
dimmer switch 
Switch for varying the brightness of a lighting installation.
switch 
Mechanism allowing the current in an electric circuit to be established or interrupted.
switch plate 
Protective plate covering an outlet or, in this case, a switch.
electrical box 
Box housing the electric connections in order to protect the part of the dwelling’s frame upon which it is mounted.