If you're vacuum has a Carpet Tool Switch that stops the roller from spinning then you have a clutch.
This metal roller assembly fits Simplicity 5000, 6000, 7000 series or Symmetry models that HAVE the carpet tool switch to turn off the roller brush while you clean.
Simplicity replacement for roller brush assembly:
C012-0600B and C012-0600
Examples of Simplcity uprights this roller brush fits includes:
7000 series: 7300 7350 7850
Symmetry models: SYM.USAFS, SYMPNT.4, SYMPNT.2, SYMP.6, SYMP.4, SYMP.2, SYM.USAFS, SYMPBP.2, S20UP, S20P