Product review (5 stars): Outstanding Dryer Duct Cleaning Kit
This dryer duct cleaning kit is awesome.  We haven't cleaned the vent in 18 years.  Wow!  I was amazed how much lint was adhered to the duct.  The manufacturer recommends that the dryer is on the non-heat setting, when I began runnng the brush into the outside opening, the lint blew out in very large amounts.  Its very easy to use.  Im very pleased with it.  I highly recommend it.