50mm x 15mm 5015 12V DC Brushless Cooling Blower Fan, Dual Ball Bearing, 2 Pin Terninal

This little fan is quiet and moves some air. I'm using it for an off-beat project, not for an electronic application, and it was an alternative to a regular computer fan. A small photovoltaic cell is enough to drive it. I am pleased with it.

Have one running for years as a cooling fan in a DVR. Bearings started making noise, so ordered a replacement, noise stopped in a couple of days. Now I have a spare. Not uncommon for ball bearing fans to make noise only to stop making noise for long periods.

Amazon needs to allow us the option of NO STARS. This is a candidate.Pretty obviously factory seconds. It worked OK and a good lot of air moving, but after ten minutes it stopped. I flicked the impeller with my finger tip and it started again.It ran for about thirty seconds and then stopped and just shivered the impeller and the center section got really hot. never would run again, just shiver the impeller.I SOMETIMES buy factory seconds, but I DO NEED to KNOW they are seconds before buying so I can evaluate acceptable risk.

Good fan, it's amazing how much air it moves for it's size. The reason I knocked a star off is because it's not controllable out of the box.Like others have mentioned in their reviews, you can make it controllable by adding a capacitor, a 220uf 16v capacitor. But it's surprisingly hard to find detailed directions or pictures of how to add the capacitor, exactly. So I will add them here, and I hope it helps someone else looking for the info.Bare with my description, I'm not the best at explaining things. I will include pics, so hopefully between the description and pics you can get it. So your fan has both positive and negative wires, red is positive, black is negative. You take the capacitor, and it too is directional, so if you look at the capacitor you will see very clearly marked which pin is negative. Make sure to connect the capacitor correctly or it will blow. All you do is connect the positive of the capacitor to the positive of the fan, and the negative of the capacitor to the negative lead on the fan. Then connect the fan as you would. That's it.

I followed the advice from Chris' review and bought this and a capacitor. After a few failed prints I realized the fan cools too well. It is cooling down the hotend faster than it can heat itself and causing an error shutting off the print. What I had to do was limit the fans speed to 10% max. 12% and above and the hotend heater can not keep up. This is a very easy change to make in Slicer and the prints have been working great. I don't know if the OG fan ever really worked but this one really blows!

I tried the capacitor mod along with using a 280uf, 2.2uf and 10uf mod but the repeiter firmwares PWM is simply too slow to give any reliable control of the fan along with a 400hz PWM modulethe capacitor mods act as motor start caps giving them the ability to start up during very low duty cycles but the fan it self regulates its own PWM to the best of its ability and there is no noticeable airflow difference between 50% and 100% on either the repeiter 15hz PWM and the PWM controllers 400hz PWMin short this fan is perfect for environments where you need to push out a lot of air in little space with a variable power supply but this trait makes it not suitable for a 3D printer's part cooling fan as it does not respond well to PWM

I bought one of these for an upgraded print head I made for my Anycubic i3 Mega S., this blower fan is so quiet, I had to actually lift it up, so I could feel the air coming out. Almost completely silent. I believe between the blower fan and the exhause fan, my printer may, MAY, be at 18db. So nice to not hear the fans running while you print. If silence is golden, this fan is worth its lack of decibels in gold.

Apart from the noise and lack of speed control it has no flaws.