DYSON BRUSHROLL  FOR CLUTCH MODELS  DC07 DC04 & DC14 & DC33
& End Caps replace part # 904174-01

Dimensions: 12 13/16" x 1 3/4" (measuring from the outside tabs on either end of the brushroll)

This is a replacement brushroll is for the Dyson model vacuum cleaners which have a clutch system.
The center of the brushroll is flat on two sides through the center as seen in the photo
If you have the dial on your vacuum that allows you to turn off the brush roll for cleaning hard wood floors,.
then this is the correct one for your vacuum.  You can also refer to the measurements listed below.  
There is a difference in size between the two different types. (non-clutch) 
 I have had a customer state he felt this product was sturdier than the Dyson brand one that came with the unit and I agree.  
This is made of hard plastic with much stronger endcaps and is built to live up to your cleaning projects.

for dyson belt click below 
Dyson DC07 DC04 DC14 Clutch model set of 2 belts