A magnetic knob is provided for use with a series of plates attached to threaded mounts which may be substituted for kitchen or bathroom cabinet door or drawer knobs. The user simply unscrews existing kitchen and/or bathroom cabinet knobs and replaces them with flat metal plates attached to threaded shafts. The metal plates are a direct replacement for the existing knobs and may not require any drilling or screwing or even use of tools. Once installed, the metal plates provide no means of gripping. Thus, the cabinet cannot be opened by a child or other unauthorized user (e.g., mentally handicapped individual). A knob provided with a strong magnet is provided so that an authorized user may attach the knob to one of the metal plates and thus open the cabinet.