SunonANBE MagLev KDE1204PKV3 40x20mm-3pin 5200RPM 6.3cfmOnly 18dBA

I paid pennies for a second-hand ethernet switch (Dell 0F491K PowerConnect 2824), it's an industrial grade switch but it had a noisy fan.I popped the switch open and measured it, and this Sunon fan is pretty much an exact drop-in replacement. Same power plug and everything.Once it arrived I was able to install it in just a few minutes. Fixed!

Great for cases when a 3-pin Noctua NF-A4x20 FLX, might not work, or just because you don't need all the "stuff" that comes with the Noctua or don't want to spend the extra money - or like black better! This is just a fan and some short wires to a standard 3pin connector - in a bag. Nothing else.Roughly the same CFM as the aforementioned Noctua, but will start at a lower voltage - handy for switches that do goofy fan speed control with voltage instead of PWM (3 pin after all).

Because of the relatively slow speed (5200 RPM) this fan is very quiet(18 dBA) while still producing 6.3 CFM of airflow. Great alternative to the Noctua equivalent.

The fan itself is a great product with OK airflow and low noise level. One of the two fans I received, in the sealed bag, was clearly used with visible dust on the fan blades and the mounting holes had already been threaded. These fans could be taken off used equipment and sold off as used. You can the the dirty q-tip in the pictures after wiping the fan blades with it. So overall, this was a poor shopping experience with the vendor (CoolerGuys) and it maybe a hit or miss if you get a new/low usage fan or one with heavy use and dirt on the blades.

Bought it expecting to replace my Synology's DS 411+ defective fan and it was a total let down. The fan depicted in the picture is the KDE1204PKV3 MS.AR.GN, but I received the KDE1204PKV3 MS.AF.GN, which sends an RPM signal to the board instead of a Locked Rotor signal. Apparently the item on the link ahead is the real deal, at least according to the reviews I saw, specially the one from Bradley N.https://www.amazon.com/Sunon-KDE1204PKV3-MS-AR-GN-40x20mm-3pin-Low-speed-5200RPM/dp/B007WLQAKE/ref=sr_1_fkmrnull_3?crid=3PJU0POYP7TN3&keywords=sunon+maglev+kde1204pkv3&qid=1550000910&s=gateway&sprefix=sunon+maglev%2Caps%2C271&sr=8-3-fkmrnullThis was my first choice, but it would take longer to arrive and I didn't have the time to wait (I live in Brazil and the person bringing it to me was leaving the US).If you want to replace the little fan on your DS411+, keep in mind that this Sunon is 20mm thick whereas the original is only 10mm, which will require you to change the screws on it or other trickery to hold it in place.1 star for the seller, 5 stars for the item, which is actually good, despite not being compatible. I will have to find something else to use it for.