No. 17659. April 8, 1970. George B. Christensen, Richard F. Vitkus, Ronald R. Baird, Chicago, Ill., for petitioners; Winston, Strawn, Smith Patterson, Chicago, Ill., of counsel. Arnold Ordman, Gen. Counsel, Dominick L. Manoli, Associate Gen. Counsel, Marcel Mallet-Prevost, Asst. Gen. Counsel, John D. Burgoyne, Janet C. McCaa, Attys., National Labor Relations Board, Washington, D.C., for respondent. Before HASTINGS, Senior Circuit Judge, and FAIRCHILD and CUMMINGS, Circuit Judges. CUMMINGS, Circuit