The Forney 72737 1-Inch Crimped Wire End Brush is a stem-mounted wire end brush with a hex shank. This brush is designed for easy access into narrow holes and confined areas. The crimped style of this brush makes it ideal for light to medium-duty. This tool is also perfect for the removal of rust, scale and paint in hard to reach areas. You can use this brush with any power drill or pneumatic air drill. This crimped wire end brush has a 1/4- Inch hex shank and a max RPM of 20,000