No. 81-1825. Submitted February 9, 1982. Decided March 12, 1982. Rehearing Denied April 20, 1982. Robert J. Mignin, J. Stephen Poor, Chicago, Ill., for petitioner, Colson Equipment, Inc.; Seyfarth, Shaw, Fairweather Geraldson, Chicago, Ill., of counsel. William A. Lubbers, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Robert E. Allen, Acting Associate Gen. Counsel, Elliott Moore, Deputy Associate Gen. Counsel, Christine Weiner, Atty., N.L.R.B., Washington, D.C., for respondent. Petition