Black Ultra Stiff Nylon Bristle Heavy Duty Power Scrub Brush for Stone 2 inch small diameter round brush with very stiff long nylon bristles. Made in the U.S.A. Great for crevices and tight spaces, features quarter inch quick change shaft,Cordless drill NOT included Drill NOT included Aggressive nylon extra stiff longbristles for stain removal and scrubbing brick, concrete, and stone Bristles are permanently set in the blocks and will not fly or pull out like a wire brush. All Drillbrush Products have a 90 day no questions asked Money back Guarantee. If you are not completely satisfied with our product we will issue a full refund or ship out a replacement at the buyer's request. Cordless Drill NOT included.