Product review (5 stars): Great product
This product worked great in cleaning out my dryer vent.  The 14 ft long dryer vent was completely clogged at a U-shaped section located in the middle of the run.  I was able to break through about a foot of lint after about 10 minutes of going back and forth through the U-shape section.  I tried this again about a year later and it just took about 5 minutes to clean the vent.  I tried a plumbing type pipe cleaner and that was a was of time.  I recommend you by the extension kit too.  I needed just one more three foot piece to reach the entire length.  The flexible pieces also work great to use to fish electrical cable between floor joist above a drywall ceiling in the basement.