A plug-in oil diffuser comprises a plug extending from a housing to be plugged into a wall electrical outlet. A non-plastic faceplate is removably coupled to the housing. The non-plastic faceplate has a cavity therein with an opening to receive at least a portion of the housing. An annular insert is disposed in the opening of the non-plastic faceplate and has an exterior secured to the opening of the non-plastic faceplate and an interior removably secured to the housing.