Clean plate and structural steel scrap 1/4 inch and over in thickness. May include heavy walled pipe split in half if larger than 8 inch diameter, large diameter pipe cut in thirds if over 24 inches in diameter, and heavy railroad scrap such as bolsters, side frames, knuckles, except car sides. Railroad wheels to be bought separately from the Bonus grade. Exclusions: All counterweights, and cast iron including but not limited to engine blocks, machinery, brake calipers, rotors, truck brake drums, etc. Free of non-ferrous and non-metallics, vitreous enameled material. Railroad wheels are to be separated for independent sale. Permissible: Attached cast iron content not to exceed 5% by weight Allowances: Alloyed steel may not exceed 15%.