Lessmann LES471217 Knot Wheel Brush 100 x 12mm M14 Bore 0.50 Steel Wire The Lessmann Knot Wheel Brushes are for grinders angle grinders and stationary machines used in the preparation and re-working of bolt fillet and butt welds. They remove scale rust paint slag rubber residue and can be used for de-burring. They are filled with a special high tensile strength steel wire in order to meet the exacting requirements during use. This Lessmann Knot Wheel Brush has the following specification: Diameter: 100mm. Width: 12mm. Bore: M14. Wire Gauge: 0.50. Wire Type: Steel. Max RPM: 12,500/min.