These brushes screw in to the endbell of a PTW motor in the same manner as the stock brushes. 
Please take care when backing out and installing plastic screws. 
The shunt wires should be routed in the side slot of the brush hood and not over the top. This allows the brush to maintain contact with the commutator as it wears down. 

The motor comm should be skimmed every time brushes are replaced for best results. Failure to do so will increase new brush wear and commutator degradation.