Product review (4 stars): Works great. The rods are surprisingly flexible and the vacuum ...
Works great.  The rods are surprisingly flexible and the vacuum attachment that fits my shop vac are great ....but only 4 stars because the rods don't quite bend well enough to make a 90-degree bend.  I had to clean out our ducts from both ends... but they are CLEAN now!  I do recommend this product!  Don't pay a contractor ...buy this DIY kit and clean your ducts more often (free after the first time, right?).