Hon&Guan 4 Inch Inline Booster Duct Fan with Speed Controller - 130 CFM Airflow with 6W Ultra-Low Power and Low Noise

I purchased the Hon&Guan 6 Inch Inline Booster Duct Fan with Speed Controller to improve ventilation in my grow room, and it’s been a solid performer. The build quality is decent, with a sturdy plastic housing and metal duct connections that feel durable and secure. Installation was straightforward, fitting perfectly into my 6-inch ducting system, and setup was a breeze.The fan works exactly as expected, delivering strong airflow to keep my space well-ventilated. The variable speed controller is a standout feature, allowing me to adjust airflow precisely without excessive noise—it's quiet enough even at higher settings, which is a big plus. I’ve been running it without any issues, no vibrations, overheating, or malfunctions.Overall, this fan does its job efficiently and reliably. No complaints at all—it’s a great value for the price. Highly recommend the Hon&Guan 6 Inch Inline Booster Duct Fan for anyone needing dependable ventilation!

This is a small but powerful exhaust fan. I am using it in a retrofitted storm shelter that is now a small home workout gym. The exhaust fan works great to create a flow of fresh air from the entrance through the fresh air pipe that was built into the shelter. The speed control is a great feature. I rarely have to turn it up past the 50% mark to get the flow I want. The long power cord is also nice to have. I would note that the power cord is on the side, so take that into consideration on how you installing this fan.

Update (1 year later)...One star deduction. The fan power supply died just short of 1 year. The fan started cycling on and off. I replaced the power supply with a 24 volt non-adjustable type and the fan is working great again. In fact, I like the air volume so much I just purchased the same model for my other son's room. The factory power supply runs extremely warm so I'm not expecting it to last. I'll be ready with a 24 volt model when it happens.I have a second floor bedroom used for PC gaming that gets unbelievably hot in the summer. Installing a booster fan in the 6" duct leading to that room mostly solves the problem. I had a 240 cfm all metal duct fan running for about three years that finally died. It was noisy and didn't seem to push as much air as advertised. This Hon&Guan model is a major improvement. Although being 100% plastic, it still easily mounts to the duct using aluminum duct tape. The claimed 345 cfm airflow is no lie. I plugged it in before installation and it rearranged all the papers in my kitchen. Compared to the twice as expensive home center metal duct fan, this one has 100 cfm greater capacity, half the power usage, adjustable speed and lower noise. My son gave me the thumbs up after a day of use. His room stays in the mid-70's (deg F) compared to 87-89 (deg F) without the fan. It is only activated when the furnace blower runs so it is not constantly on. If it lasts a few years I'll be very satisfied.

Definitely made a difference in the room. Easy to install and works great. It runs quiet until you put it in the duct, then it becomes louder. Worth the noise to cool the room down.

I was suggested this fan by someone and they were right. It is the best quality one you can get. I buy everything cheap and there were cheaper options but im very glad I got this one. Extremely quiet and fast air flow. Great adjustability

At first this duct fan worked well it moved air efficiently and was fairly quiet, making it useful for small spaces and light projects. However, it’s not built for heavy-duty use, and unfortunately mine stopped working after just one month. It’s fine if you only need something temporary or light-duty, but not reliable for long-term use.

Great fan, I used it for a DIY project completely unrelated to what it is designed for and it worked great for me. The project didn't work out, but not because of the fan. I would definitely purchase this unit again.

Got this to vent resin printer fumes out the window. After messing around with it a bit it seems like it's up to the task.[UPDATED REVIEW 5/5/24]To stress test the fan a little, I left it by the window for 2 days, running non-stop at half power. Not exposed to direct sunlight or rain, on a level surface, etc. Normal working conditions. The fan eventually developed a rattle, like the fan is unbalanced or something. The rattle comes and goes. It's still quiet enough that the hose and enclosure mostly muffle it, but it's definitely concerning, and disappointing considering the good first impression it gave me. Maybe spend the extra 2 bucks on a metal exhaust fan instead, assuming those are sturdier.[CONSTRUCTION]This 4-inch inline fan is made of lightweight plastic, including the blades. Its tough not to be snarky and say this is basically a glorified computer fan, but that's the impression it gives because of all the plastic.The housing is sturdy though, it won't flex unless you're cranking down on the hose clamps at the ends (hose and clamps not included).This is actually one of the nicer products I've bought from Chinese manufacturers, it doesn't have that worrisome "cheap" feeling.If the plastic is a dealbreaker for you though, there are def more options in the same price range that have a metal housing instead, with varying CFM.This unit comes with a stepless dial-like controller to adjust the fan speed.There are no guards over the fan blades so don't stick your fingers in there, and don't leave it out for curious pets to play with.[NOISE]This fan can be quiet and noisy depending on the power level. When set somewhere between 45%-90% power there's an underlying mechanical whine. It doesn't sound like anything is loose or broken, it's more like the sound a jet turbine naturally makes as it ramps up in speed. I actually think it sounds cool, but I can understand why some people don't like it.Without the whine it simply sounds like a strong computer fan. I could sleep with it in the room, but maybe not at full speed.Playing with the speed controller is almost therapeutic. Don't bother with fidget spinners, get one of these fans instead![IN USE]I used this to ventilate a small resin 3D printer enclosure, and the 130 CFM Hon&Guan claims for this unit is more than enough for the task. I can set it to under the 40% power mark (where the mechanical whine starts to be noticeable) and it's still effective. I have a short hose though, if you're running a hose across the room you may need more power, or even a second inline fan. (There is a 6-inch version of this fan available if you need a lot more CFM.)I left it running at max power for a few minutes and haven't noticed any hot spots on the fan housing or controller, but I will keep checking on that.If you're using this fan to vent fumes, VOCs, etc., be sure the air you blow out the window isn't being blown back in by the air outside, or getting sucked back in through a different window haha. Also maybe consider putting some netting over the exhaust end to keep bugs from getting in when not in use.Another tip, try to install the fan as close to the window as possible. What you want to do is have the fan pulling air out of the hose/enclosure, not pushing it through. Pulling air prevents the polluted air from escaping from any leaks in your ventilation system, while pushing air through the hose will push it out of all those leaks along the way.[RECOMMENDATION]This is one of the cheapest and most streamlined options for resin printer ventilation on Amazon, and thankfully it works great. I will update this review if I find any long-term issues.