Product review (4 stars): These are great to clean metal tubing
These are great to clean metal tubing, but not the thin walled flexible tubing that should only be used from the dryer to the wall. I had some remodeling done about 6 years ago and we moved the dryer to the middle of the house the contractors ran 25 feet of the thin walled corrugated tubing through the finished basement ceiling. I tried to clean the tubing with this kit and quickly put a hole in the tubing. I replaced the tubing with a semi ridged metal tubing. I'm glad the dryer was protecting its self since the old tubing with its accordion rough sides had completely clogged up.