Dyson DC07 - Leftover rubber seal after replacing motor?

I recently replaced the motor on a Dyson DC07, I now have a rubber seal leftover and I don't really know where it goes. It is circular and has a 14cm diameter. It has two cuts along the edges. I've posted a picture here http://img169.imagevenue.com/img.php?image=07714_IMG_0295_122_45lo.jpg

Thanks for any suggestions