Eversimpleinc Dryer Plug Adapter with Green Ground Wire, Connects 4-Prong New Dryer Female to 3 Prong Old Dryer Male Receptacle, What Is a Three-Slot Dryer Outlet? Before 1996, it was standard practice for 240-volt clothes dryers to have three-prong cords that plugged into 240-volt outlets. Fred’s Appliance Service is capable of installing a new 3-prong or 4-prong cord on either your dryer or range. Schedule service online today !