iPower 4 Inch Inline Booster Duct Fan 100 CFM HVAC Exhaust Ventilation Blower with Low Noise for Grow Tent, Basements, Bathrooms, Kitchens and AtticsRecycled Claim Standard 100

The duct fan works extremely well and quiet. When it started to run I could not hear it so I had to put my hand on the housing to feel the slight vibration from it to confirm its working. I installed two of the 6 inch fans on two separate duct runs to one room that was always cooler by 4 degrees. After installing the duct fans all rooms are of equal temperature. I gave them 5 Stars for quality, CFM and low noise.

This fan has a decent air flow, it seems to produce the airflow you should have been getting without it. I installed it in line. But there is no speed controller, if you plug it in it runs at full speed. So I installed dimmer switch.

I have rated this fan a 5 on price and value, however if you are considering buying this fan for use in your home or office space then read the whole review because this probably isn't right product for you.This is a great fan for the price, it moves a lot of air for the money, made of quality components for the price, but it is VERY loud.If you are planning to use this inside a living space or office, seriously think twice about your purchase. As soon as I turned it on, I instantly had buyers remorse as it is not for my application. I have it inside a 2' x 4' grow tent in my living room. This thing runs at 48 decibels, and it is comparable to my wife's hair dryer running on medium but with a lower pitch. I have it hooked up to a smart switch and can turn it on from one of the upstairs bedrooms across the house with the door closed and hear it turn on and run. Unfortunately due to the price, it has no speed control so you get all or nothing. If you are planning on using this fan in an attic to boost an HVAC duct, or in an industrial/warehouse setting this would be a perfect fan and I highly recommend it for those applications. But for a grow tent in a living space, I can't recommend it.I can't fault the company for my mistake in buying this fan, the product page clearly states accurate specifications of the fan including the decibel rating, and overall it is a great product for the price. Just not the product I needed, and you might not either. I have ordered a separate AC speed controller and a duct muffler which should reduce the sound by half, but for the cost of all that, I could have gotten an AC Infinity fan that would better suit my needs right out of the box.

I wish it pushed a bit more air and had a variable speed feature.

I bought this to put in my cats room so it could get the smell out and it actually works very well and it’s really quiet so it doesn’t bother me or my cats

P while I'm not using this product because it was bought by mistake or didn't need it anymore unfortunately, however I've seen this product before which is why I wound up in my cart. If you're looking at a product like this and no what you're looking for, I definitely would say go with this one. As far as I know this is the one I would have went with

Fan blades cannot even push air past a few inches. The metal design feels nice and durable, but the item serves no real function. Noise level almost as minimal as the airflow.

I'm using this 4" inline fan to vent a powder room. As received, it powered on nicely, has a pleasant white noise, moves about 30-40 CFM (compared to a typical 50 CFM ceiling mount blower) and guessing approx 1.0 zone noise level. It had a very slight vibration that wasn't cause for concern but I addressed it anyway.The fan connects perfectly to 4" aluminum ducting.I disassembled it to check it's serviceability, if it should ever need cleaning or bearings serviced. I found the fan blades wobbled +/- 1/8" (3-4mm) from the base plate being deformed during initial installation. They are soft aluminum and can easily be bumped out of place, since they don't have much form to keep them rigid.I spent a little time spinning the fan and adjusting the blades. A marker helped find the high spots, and adjusted with pliers. To balance the fan, I used a patch of duct tape. I moved it to each blade, noting if it increased or decreased the vibration. I then applied a little strip of aluminum tape on the lightest side, and trimmed it till it was reasonably balanced.Digging deeper, I discovered it has ball bearings, which should last longer than sleeve bearings, but depends on the quality of the ones installed. There's a slight coarseness to them, but only if your ear is right on it. Personally, I like that I can replace these bearings when they go out instead of replacing the whole motor assembly.Overall it's a decent fan as shipped, perhaps a little ambitious with it's CFM rating, but it does rotate slower thus giving a more pleasant sound.