Review on 🌀 VIVOSUN Adjustable Inline Ventilation Controller by Eric Avina

I have 2 of these. I'm so impressed with how quiet they are and still blow a lot of air, I still have 2. I have a few more expensive fans that are replaced with these for noise reduction. Edit: 4 months these fans have been running 24/7 with no issues. I might add that I run them at about 3/4 speed and unhindered. If you reduce the speed, the fan motor revs up and the wind noise increases. The engines are fast but weak, so in the absence of obstacles they blow a lot of air, but choke easily. So good for venting a small box, but not so good for a charcoal filter. Although works with a small filter. Edit March 2018. It's been almost a year now. 2 of these fans run 24/7 and 2 of them are on and off for ventilation. No problems with any of them. They are all still extremely quiet and I have not noticed any loss in performance.