In summary, there are three types of relays; reed relays, solid-state relays, and electromechanical relays. KEMET is offering the electromechanical type signal relays in particular. Signal relays control signal flow, using an electromagnet to actuate the state of the switch. They are available in latching and non-latching types. Typical applications for signal relays include the control of industrial machinery and control of signal flow in commercial and telecom applications.