WINSINN 40mm Blower Fan 12V, 3D Printer Micro 12 Volt Fans Blower 4020 Hydraulic Bearing, 40mmx20mm 2PIN (Pack of 4Pcs)

I bought these for a custom cooling system I was working on.I was surprised by how quiet they are.-Now the PSU is the only noisy item left-

These fans seem to work ok. But you might need to solder them. Two from the factory didn't work. Both had wires detached. One was missing one, the other both weren't soldered. It didn't even look like they were soldered on to begin with. It's easy enough to do, if you have a basic soldering iron. I don't consider any new product that I have to immediately repair, to be a good product. Just tin your wire, heat the solder blob, and then let them cool together.Once you fix them, they blow very well. I'm using two on a 3d printer, as a hotend fan, and the part cooling fan. Of all my problems, I don't think these fans are part of it.If you wire these up backwards, they won't blow. Usually DC motors will run backwards, but these don't. Even if they did work backwards, blower fans like this can't work in reverse. Physics thing, not an opinion.Pay attention to the wire colors on the fan, and make sure they match up to your wires. One of my connections was wired backwards, so it simply didn't work. Once I reordered the pins, it worked perfectly.

These fans are loud and seem to be lower quality in general. I've used fans from 3010 to 5015 purchased from WINSINN and never had an issue until these. They are for some reason louder and the soldering was very poor. The black wire was holding on by a thread and a slight tug on the red wire and the whole thing including the pad came off.I'm pretty disappointed in these. Hopefully it was just a bad batch.

Works as should but can break if over tightened

These fans came well packaged, and are exactly what I wanted.

Works as expected (pretty sure it hauls more air than my stock fan), but it's really loud, especially at max power. Since I used this for my SidewinderX1, a workaround is to not use the fan at max power unless needed. If you're using PrusaSlicer, you can go under Filament Settings -> Cooling and Enable Auto Cooling. It'll only run the fan at max power for bridges / overhangs.

I used these for fans inside a cosplay helmet to help from the lenses fogging and too help keep me cool, and they do just that. I have them hooked up to a 3 AA battery pack and they last for a good amount of time. They are a little noisy and I did have to create a cover to keep my hair from getting caught in them, but that's due to the application I utilized them for and not any fault of the design or manufacturing.

A little noisy, but not bad for radial fans. But do they move some air! I use them on my 3D printers and they are some of the most powerful fans I have tried. I rarely run the speed past 60%, but with dual fans on at 100%, I can print overhangs with pla that I didn’t think were possible. Even better than dual 5015 fans.I have a couple hundred hours on the fans on my CoreXY printer and they show no signs of degrading. Very happy with them.

I bought these to upgrade my part cooling fan on my Tronxy X5S 3D printer. The original 4010 fan was like an asthmatic bluebottle and more of an ornament than a functional fan. I designed a new fan duct to suit this blower and it has transformed the cooling ability. The fan does seem to rotate the wrong way to my mind, with the curved blades of the centrifugal fan seemingly pointing in the opposite direction to rotation, however it does work so maybe I'm wrong in believing it should go the other way. They're sleeve bearing so not sure how long they'll last but I've got 3 spares and the first one is still going strong after around 200 hours of use so I'm happy so far. For the price I can't give less than 5 stars. Just wish they'd do a roller bearing version.

Terrible. 2 of these dead on arrival (well, they barely spin), 2 just noisy and horrible. The speed is so variable, even with constant input.

They blow as expected. For how long, only time will tell!

Okay to begin with, bearings went after a couple weeks.

Package of 4 fans came with only 1!! working fan! Waste of money.