Product review (4 stars): Worked just fine!
Worked very well and beats the $200. for a company to come in and clean the vent. There are a couple of ways to clean the vent. I needed to do it from the outside of the house. I was confused by the written directions included and almost returned the item. I decided to look on y-tube and found just what I needed to do presented in a simple fashion. Worked like a charm and vent is clean.  Delivery was quick and item was packaged well.
(A shop vac helps the procedure along and there are adapters for the shop vacuum if you have one of the smaller types which I do)