Black Diamond, 50 LB, Medium, Blend Coal Slag Sandblasting Abrasives In BlackWhite Bags, Superior Cleaning Ability, Thanks To Hard, Angular Particles That Enhance Speed Cutting, Low Free Silica Content, Low Dusting Consistent Uniform Weight, Chemically Inert Hard Angular Pieces Enhance Speed Cutting Very Low Friability Means Less Fracturing Or Splintering Consistent Uniform Weight Gradation Ensures No Clogging Low Heavy Metals