Applies to outlet circuit testers, ground-fault circuit-interrupter testers, and similar indicating devices that are: (a) For use on 15- and 20-A, 3-wire, 125-V receptacles, (b) Intended to be connected to the receptacle for a period of time only as long as is necessary to note the indicated pattern of lights or other similar indicating means, and (c) Not intended to be a comprehensive instrument or to determine the quality of the circuit grounding. These requirements also apply to retention testers and other indicating devices with a retention testing capability that are intended to indicate the force exerted on the blade or blades of the tester by the contracts of a receptacle.