VIVOSUN 4 Inch 100 CFM Inline Duct Fan - Low Noise HVAC Exhaust Ventilation System for Basement, Bathroom, Kitchen & Attic - Silver | Perfect for Home Ventilation, Grow Tents & Indoor Air Circulation

With a filter over incoming air this provides previously wasted heat from attic space into living space. Easy, clean, quiet, inexpensive way to reduce unnecessary carbon based heat source.I ordered the wrong size :/Solid craftsmanship and pretty powerful. Keeps air fresh without a lot of noise and don't cost much to run.I installed this a month after i received it as a way to vent my Kitchen coupled with a smart fan controller... it worked better than most hood vents but would not achieve full speed and would begin to sound funny... i only ran it at mediumm speed for maybe 1hr every day... one day last week, i pushed the button and got nothing... now i have to go in the attic and check it out...:(Pulls alot of air into the room I made from the existing ac ducting. With how much air it moves, I can forgive the noise levelGot these for a client to use with a mini split running 3 ducts. The ducting is in the attic so the noise is not heard but even when standing next to the duct, its hard to hear.The cords are decent length and since all the fans were installed in the ducts near each other, I was able to install a double outlet box in the attic to plug them all in and run a switch near the thermostat for when the fans are needed.Helpful, but not very powerful. Moving air through an empty 6-inch duct and not much flow. Perhaps as an assist it might be better, but as a free air blower, not so much.Extremely loud and after short time has started to make a loud rattling noise that sounds like something is broken off. The company is awful to deal with aswell. I’ve contacted them with my issues and was told I would receive a refund and then they completely disappeared and would not answer my emails, very shady. Low quality products and service from this company is all I’ve ever experienced.Absolute garbage. Bought 2 and the first one I plugged in buzzed and didn't even turn. This is the kind of thing that can burn your house down.I love seeing people complain about this guy. Its a 100cfm duct booster. Whats not to understand. NO THIS WILL NOT WORK WITH A CARBON FILTER. NO THOS WILL NOT WORK WITH A DIY FILTER.It is mearly a very small booster fan for long runs of 4 inch venting. I currently have it set up on the end of my 30 ft intake vent for fresh outside air. It is just barealy bringing air in, but thats what i want.I guess that's a no-go for this item. I don't know if it is just this one unit but after a few days I noticed an annoying noise. I'll try another model I guess.6 months old, bearing gone in output shaft, fan extremely noisy, month outside of return. would NOT recommend. no way to contact seller to see if issue can be resolved. will keep posted.