Glass bead sandblasting media is used for surface cleaning and peening, producing a matte finish. It is less abrasive than aluminum oxide or steel shot. #12 glass bead is 140-230 mesh size. Diameter is approximately .0041"-.0025". Choose the appropriate grit for the application. Winona Van Norman sells glass beads from large size #1 to very fine #13 as well as various grit sizes of aluminum oxide and steel shot.