Construction Tools - Medium, Stiff, Ultra Stiff Scrub 3 Brush Kit - Threaded - 5/16 x 24 - fits Electric - Cordless - Air Pneumatic - Dual Action - Orbital - Rotary - Buffer - Polisher - Machine Threaded Shaft 5/16x24 brushes to fit Polishers and DA machines Three of our most popular professional brushes in a multi-use kit Made to fit Electric and Air Pneumatic Dual Action Rotary Polishers and DA machines Contractor grade Large 5 inch diameter brushes: Stiff Red, Medium Green, Ultra Stiff Black Drillbrush Products have a 90 day no questions Money Back guarantee If not satisfied with brushes