Brush Cover replacement Set
It's surprising how many people break these. They hold the brushes in place on the sides of the motor, and if you break them while you are checking or changing the brushes (which lots of people manage) then your only option is to wrap tape around the motor to hold the brushes in place.
Its a poor design, and they ARE easy to break. But the good thing is that once you've broken the first one working out how to remove them, you'll never do it again.
These handy caps will replace the broken ones!