List of catalogue numbers [ BC52171-K ] 4IN SQUARE BOX 2-1/8IN DEEP KO [ BC72171-K ] SQ BOX 2-1/8IN DEEP KO 42 CU IN [ BC52151-K ] 4IN SQUARE BOX 1-1/2IN DEEP KO [ BC52171-KSSX ] 4IN SQ BOX 2-1/8IN DEEP STEEL 30CU [ BC52151-KSSX ] 4IN SQ BOX 1-1/2IN DEEP STEEL STUD