Pictured here is a new 700 model CHM that has a few mods performed to enhance performance.  First some thermal tape was installed on the brush motor to prevent the entry of debris into the internal parts of the electric motor to help prevent early failure of the  two electrical brushes that make contact with the armature.

Second, the two stock brushes were modified to enable easier cleaning after a cleaning mission.

Third, three sealed ball bearings were installed to prevent the entry of debris into the brush gear assembly.