[ Cables, electric; Circuit breakers; Current rectifiers; Digital multimeters; ] Electric connections; Electric meters; Electric relays; Electric switches; [ Electrical distribution boxes; ] Electrical plugs and sockets; Inverters; Power supplies; Sound alarms; Surveying instruments; [ Time switches; Transducers that utilize ultrasonic oscillations to test for stress and fatigue in metal and metal structures; ] Transducers that utilize ultrasonic oscillations to treat and reduce stress and fa...