Replaced the rubber brushes and started the vacuum. He made a lot of noise, checked the brushes, they fit, but when the vacuum came on it made too much noise. When I paid attention, I noticed that the brushes are not spinning at the right speed, but are jumping and making noises. I then pulled out the rubber brushes and compared to the original brushes and they are slightly smaller which causes them not to rotate. It doesn't cost any money. I need to find a way to return or replace the brushes or find other proper brushes. I recommend at least not for i7.