Product review (1 stars): Restricts airflow based on testing
I bought the item, intending to install it due to the positive reviews, but then I watched a video on Youtube that tested the air flow efficiency.  It turned out to be one of the worst performing dryer vents.  Less air flow means taking longer to dry clothes.  I returned the unit. I'm sticking with the basic louvered style vent for now.  The video is titled "How to reduce your clothes drying time and save energy costs"