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Question: Do they also work in the roomba 790?  How often do we need to replace these brushes?  Thanks.
Document: I was a little concerned when I opened the box after receiving these side brushes. A couple of the brushes were a little bent out of shape, but after I put the  brushes on my Roomba they eventually straighten out & work great. I have a iRobot Roomba 700 Series. Very happy Amazon sold these.
I am using these with the 770 roomba. They work, they are a good price... what more could you ask for?
I was a bit surprised to find the original one broken after only a few months of use and ordered this item from Amazon to replace the brush. I have been 100% satisfied with the replacement brush and the Roomba works as before. The only caution I advise is that the package in which these brushes are shipped from China is extremely small and difficult to open. I used a pair of scissors to cut it open and accidentally cut off the bristles from one of the six brushes enclosed therein.
My original brushes needed to be replaced. These are the same as the original brushes that came on the Roomba when I bought it.
Two brushes came broken right out of the package. They are a noticeable lower quality than the original roomba brush.
These were a great price, when i got them first thing i thought was funny was within the amazon box the brushes were still in the little mail pouch from china with the customs label on them, there is not really any packaging beside that so very grey market.As far as for fit and function, they are the same size and look the same as the genuine roomba brushes.
This item actually has five brushes, not three. Cleans better than the three brush ones. But, item takes forever to get to your house after purchase.
I received th brushes in a timely manner and installed them easily. I got the pack of 6 brushed because the original brush only lasted about a month using it on a daily basis. I believe it is due to the design of the machine. when it spins it hits the wheel about half way up the brush and I guess after prolonged use, the little brushed can't  take the constant battering then they break off.
Parts Fit perfect . Love my Roomba. Couldn't live with my dogs without my Roomba fast delv of parts are nice
After about 16 months, the side brush on our Roomba fell apart. It runs 5 days a week, so no complaint there. In looking around for a replacement, these looked like a great value for the price, if they were any good. I am pleased to say that they appear to be the same quality as the original, and our Roomba is back up to full function. Very pleased.
Answer: I think they will work for all series 7 roomba models. You might need to replace them every six months out so.