Product review (2 stars): Quality control?
I bought this because it was required to have it for a new dryer installation from a major retailer.  This was significantly cheaper than the retailer was charging for a comperable product.  The dryer vent is good but the included tension clamps were 3" and not 4".  I thought the installer was joking, but sure enough, they were definitely the wrong size.  Maybe, I received a defective/mismatched set.  Luckily, the dryer installer had a spare set of tension clamps on his truck that he provided for free..