Burr-Rx Wheel Brush, Small Diameter, 1-1/2 in Brush Dia, 3/8 in Face W, 1/2 in Arbor Hole, Crimped/R Small diameter Burr-Rx wheels feature Weiler advanced black ceramic grain filament which delivers up to a 400% greater edge cutting action in comparison to traditional silicon carbide and aluminum oxide filaments for the fastest, most aggressive deburring action for minimum cycle times and maximum media life..