Product review (4 stars): Good quality duct.  Didn't use the clamps.
Definitely an upgrade over the last flexible foil duct I purchased, which literally disintegrated after six years.  I strongly recommend buying a metal elbow to potentially prolong the life of this product.  My old one failed at the bend, as the dryer is near the wall and the old duct had to bend 90 degrees immediately off the back.  The foil on this duct is much thicker, but it is still an inexpensive addition to the job and made installation easier as well.  I didn't trust the clamps and bought screw clamps instead for a few dollars more.