Brass cup steel brush - Diameter: 50 mm. -1/4" spike. -With "0" brassed steel wire barbs.3mm -Use in normal drills, maximum 4500 R.Q.M. -Ideal for polishing oxidized surfaces in general, polishing welding slag, removing varnishes, removing small scales in general. -Article known as paint cleaning brush, rust cleaning brush, metal polishing brush, paint lighting brush, rust removal brush.