I don't know - but before you go to the trouble of dismantling the machine (what symptoms do you have that make you suspect the brushes ? you don't say) consider that there may be a fault in the cable - at the plug end - constant tugging over time gradually stretches the inner conductors until they break apart - it takes just a few minutes and no cost to shorten the cable by 6" or so - I have fixed half a dozen cleaners this way - never needed to replace brushes - not yet.
Failing brushes - before they die - generate heat and a noticeable smell - the motor runs roughly.
Good luck...
Peccavi
August 2010