A cheater plug, AC ground lifter or three-prong/two-prong adapter is an adapter that allows a NEMA 5-15P grounding-type plug to connect to a NEMA 1-15R non-grounding receptacle. They are needed to all
A cheater plug, with metal grounding tab (lower right). The ground tab is designed to be attached to the outlet faceplate screw, which is supposed to be connected to the building electrical ground.