High impact twist knot wire brush. Used in surface preparation prior to welding and for removing weld scale, spatter and heavy corrosion. Used for heavy duty cleaning applications. Arbor: 1/2" - 5/8"; Wire size: .020" (.50mm). Maximum rpm 9,000. WIRE WHEEL BRUSHES Dia\In=6 5/8" - 11" ARBOR TWISTED/KNOTTED