15 AMP 4 Way Decora Switch
The four-way switch is used in between two three-way switches to provide control for an outlet or light fixture from three or more different locations. If you want to have control from more than three locations—say five locations—you would still use two three-way switches (one on each end) and three four-way switches in between the two three-ways.
The four-way switch looks similar to a double-pole switch, except it has no ON or OFF markings. It has four terminals (plus a ground), usually brass-colored. There is no COM or "common" terminal, as in a three-way switch. The four-way switch simply functions as a switching device for the traveler wires between the three-way switches.