Relay Sockets & AccessoriesA relay is an electrical switch that is activated by an electric current or voltage. It is often used to control a circuit with a lower voltage than the one being controlled. A relay socket is a device that holds a relay and allows it to be easily installed in a circuit. There are many different types of relay sockets, each designed for a specific type of relay. Relay sockets often come with accessories such as mounting hardware, terminal blocks, and protective covers.