VIVOSUN4 Inch 25 Feet Flex Air Aluminum Duct for Ventilation, 2 Clamps Included, Long Heavy-Duty Multi-Layer Dryer Hose Vent Kit, Duct Fan Systems

My portable ac unit vent broke so I bought this one and it works create. See picture. Material seems to be of good quality. it has clams to clamp both ends. Looks great with black color. Very easy to install, just open up and pull everything comes out. Light weight and it woes as expected. Just tighten the clamps at both ends nicely.

I got two of these air ducts for my basement ventilation. My house has no Radon mitigation system, so I want to use a simple way to ventilate the basement. A window fan blows air out at one basement window, and fresh air comes in from another window. But the windows are too close to each other, so I have to use air ducts to let the fresh air to travel about 40ft to the other side of the basement so that the whole space is sufficiently ventilated. I connected two ducts to reach the length. I used hanging straps to hang the duct to the ceiling wood so it's out of way. Now the radon detector shows the level fluctuates between 4 to 9 in the basement. Before ventilation, it reached 20 to 50! The living spaces upstairs has radon levels ranging from 0.2 to 1.0 most times, well below the 4.0 threshold.The side effects of the diy ventilation method is the lower basement temperature in winter (around 50 F) and higher humidity in summer (I run a dehumidifier in basement anyway, only that the electricity use is up).Back to the ducts, they are flexible, easy to expand and shrink in length, easy to install, the aluminum foil is thick. The price is reasonable.

Works great! Used it on a portable A/C unit so my wife could move to her sewing room and then back to the bedroom. Made her happy, which makes my life easier. Definitely would purchase again.

This product is incredible! It functions perfectly and exceeds expectations. Highly recommended!

Price and quality

Very good quality ducting. I purchased this for my 4inch inline fan & Carbon filter. I ended up purchasing way more than I needed. So Ill have plenty left for the next project. Flexes easily and is durable.

Just as described...time will tell if they last..

Good quality. Fast delivery. No issues installing.Would buy again.I got the thumbscrew clamps. They are also awesome to use.