On A 3-way, there’s an extra terminal, called the “widespread.” Power is available in to the switch over the prevalent, then two “traveler” wires link the very first switch to the second on the brass terminals. HomeTips content articles may have links to Amazon.com as well as other associate applications https://smartswitches75284.blogadvize.com/42383167/smart-power-points-and-switches-an-overview