Features: * Made of .020 carbon steel for strength and durability * Can be used at maximum speeds of 14,000 RPM * Arbor size 5/8-inch - 11 * Two arbor adapters are included for use with a variety of tools What"s In The Box: * Mercer 189010 2-3/4-inch Knot Cup Brush * 5/8-inch-11 to M10x1.25 Arbor Adapter * 5/8-inch-11 to M10x1.5 Arbor Adapter