Old rsj sizes. So 18" x 7". 4 2. RSJ 18 x 7 1/2 x 75# RSJ 20 x 7 1/2 x 89# RSJ 2...

Old rsj sizes.  So 18" x 7". 4 2.  RSJ 18 x 7 1/2 x 75# RSJ 20 x 7 1/2 x 89# RSJ 2...Old rsj sizes.  So 18" x 7". 4 2.  RSJ 18 x 7 1/2 x 75# RSJ 20 x 7 1/2 x 89# RSJ 2...