Product review (5 stars): Gardus Linteater Vent Cleaner
Fantastic tool! We have a 29 ft dryer vent with an "S" at each end located in a barely accessible crawl space.  The Gardus system with the extension rods in combination with a shop vacuum and a leaf blower made the job easy.

Highly recommend this tool.  Buy the extensions rods if your vent is over 12 feet.