It seems that I forgot to mention that the complete set they need is a SCR-274N. Thanks, Taigh Taigh Ramey Proprietor, Vintage Aircraft 7432 C.E.Dixon Street Stockton, California 95206 (209) 982-0273 (209) 982-4832 Fax www.twinbeech.com KEEP 'EM FLYING...FOR HISTORY!