On A 3-way, there’s an extra terminal, known as the “widespread.” Power is available in towards the switch on the common, then two “traveler” wires connect the 1st switch to the second about the brass terminals. One example is, the BS 1363 plug is used in the United Kingdom, when https://angelodypgv.ampblogs.com/details-fiction-and-smart-light-switches-71456776