Reflective Glass Bead Type 1 with a "Powder-like" texture. Similar to the reflective glass beads used on street signs, curb marking, arts and crafts. (These beads can also be used for preening and sand blasting.) Recommended for drop on(reflective) applications. Do not mix into paint. Makes paint reflective. Beads are sprinkled on top of the wet while it is still wet. DOT recommends a ratio of 6 pound beads per gallon of paint. (covers 100 Square Feet) Size is US Mesh 100-200, (125-150 microns), Mil-Spec 10/11, Roundness 65 to 95%. Refractive index is >= 1.51.