Product review (5 stars): I did duct tape the joints which is a bit of a pain to do but better safe than sorry
Previous owner of our house had let the dryer vent get completely blocked. I bought 2 of these as I had a long duct. Had to work it from both ends and then used a leaf blower inside the house to blow out the remaining fluff (thanks to a prior reviewer for this tip!). I did duct tape the joints which is a bit of a pain to do but better safe than sorry.