. . . Exhibit 21 Subsidiaries of the Registrant State or Other Jurisdiction of Subsidiaries Incorporation - ------------ --------------- Ault Incorporated Minnesota Ault International Trade Shanghai Co., Ltd. China Ault Shanghai Electronics Co., Ltd. China Ault Xianghe Co., Ltd. China Cedar Corporation Nevada Cedro de Mexico, S.A. de C.V. Mexico Condor D.C. Power Supplies, Inc. California Condor Holdings, Inc. Delaware Condor Power Supplies de Mexico, S.A. de C.V. Mexico Industrias SL, S.A. de C.V. Mexico MEX Holdings LLC Mexico MTE Corporation Wisconsin RFL Electronics Inc. Delaware SL Auburn, Inc. New York SL Delaware, Inc. Delaware SL Delaware Holdings, Inc. Delaware SL Montevideo Technology, Inc. Minnesota SL Power Electronics Ltd. (a) United Kingdom SL Surface Technologies, Inc. (b) New Jersey SLW Holdings, Inc. (c) New Jersey Teal Electronics Corporation California TPE de Mexico, S. de R.L. de C.V. Mexico Waber Power, Ltd. (d) Connecticut All of the subsidiaries are included in the consolidated financial statements for the year ended December 31, 2006. (a) Formerly Condor Power Supplies (Europe) Ltd. (b) Formerly SL Modern Hard Chrome, Inc. (c) Certain net assets disposed on August 29, 2001, and name changed from SL Waber, Inc. on September 10, 2001. (d) Formerly SL Electrostatic Technology, Inc.