... 7)Shot GradeApproximateSizeFinishApplicationsS-700.007"Fine, smooth shot finish. Excellent coverage.Blasting of relatively small ferrous and non-ferrous castings. Removal ... .017"S-2300.023"Medium, light shot finish. Good coverage.Blasting of grey iron, malleable iron, light steel castings, ... "S-3900.039"Average to heavy shot finish. Average coverage.Blasting of steel, heavy malleable iron and grey iron ...