No. 7347. Argued January 22, 1957. Decided March 11, 1957. Arnold Ordman, Atty., National Labor Relations Board, Washington, D.C. (Theophil C. Kammholz, Gen. Counsel, Stephen Leonard, Associate Gen. Counsel, Marcel Mallet-Prevost, Asst. Gen. Counsel, and William J. Avrutis, Atty., National Labor Relations Board, Washington, D.C., on brief), for petitioner. Louis R. Becker, Washington, D.C. (Edward T. Cheyfitz, Washington, D.C., on brief), for respondents. Abraham L. Friedman, Newark, N.J. (Samuel