Specification :

Steel shot refers to spherical grains made of molten steel through an atomization ( " granulation" ) process, available in different sizes and hardnesses.
Surface preparation is as a series of operations including cleaning and physical modification of a surface. Steel shot and grit are used in surface preparation process for cleaning metal surfaces which are covered with mill scale, dirt, rust, or paint coatings and for physically modifying the metal surface such as creating roughness for better application of paint and coating