Efficient, long-life aluminum oxide in a hard ceramic bond for general purpose polishing, light deburring and smoothing of rough castings. This media is made up of 1/4” x 3/8” triangular shapes and provides a high luster finish. Ceramic meida works well on both soft and hard metals, aluminum to stainless steel. Choose the shape that best matches the contours of your part and a size that's large enough not to lodge in recesses and holes. 49.6% silicon dioxide (SiO2); 40% aluminum oxide (Al2O3); 5.5% potassium oxide (K2O); 2% sodium oxide (Na2O); 0.4% iron oxide (Fe2O3); 2.5% calcium oxide (CaO)