Blast Media, Abrasive Media Type Walnut Shells, Grit Not Rated, Container Size 50 lb, Compatible Mesh Size - Minimum 12, Compatible Mesh Size - Maximum 20, Compatible Blast Pressure - Minimum 40 psi, Compatible Blast Pressure - Maximum 100 psi, Number of Cycles - Minimum 1, Number of Cycles - Maximum 2, Container Type Box, Particle Diameter - Minimum 841 micron, Particle Diameter - Maximum 1,680 micron