The brush knots are knotted to 75% of the length. The brush is designed for brushing large areas and for heavy-duty brushwork, such as deburring, cleaning, derusting and descaling, as well as removing spatter. Brass wire filament brushes are designed for applications like surface finishing on copper or brass workpieces. Compared to steel wire, brass wire is softer and more flexible. For all brushes with brass wire, PFERD uses wire quality CuZn37. Brass wire is temperature-resistant up to 350°F.