4PCS Pro Micro Atmega32U4 5V 16MHz Bootloadered IDE Micro USB Pro Micro Development Board Microcontroller Compatible with Pro Micro Serial Connection with Pin Header

My brother and I were re-learning how to solder and found a fun project to make our own low-profile open-source keyboards. The keyboard project required this form-factor of board, and these were the more money conscious options out there.The micro-USB interface isn't ideal for long-term use, as it was recommended to me to make sure I'm not unplugging-replugging the cables in many times. If I can have them plugged in and then keep them plugged in they will likely last longer.If you're looking for potential projects using these boards, there are a ton out there! Many open-source projects exist which require these 24-pin boards. If you like to solder and want some projects to use those skills with this would be a great place to start.I would recommend grabbing a board that uses a USB-C interface, but ultimately these are great microcontrollers on a budget, and a great place to start learning how to program and use them.

The Micro-USB version is not very durable because the female port can tend to break off the PCB if you aren't careful with it, but the Mini-USB version completely fixes that issue. The Mini-USB jack has more solder points the PCB and is much more durable. While it is true that Mini-USB cables aren't as common as they used to be and not everyone has them laying around, they are still readily available here on Amazon for low prices. Even if you need to buy some Mini-USB cables, it is completely worth it for the more durable and reliable connector.

These work wonderfully. The USB socket could be stronger, because a bit of force will bend them. I bent one really bad just by uploading sketches often and removing/inserting the cable. Also, you may need to touch a piece of metal between the reset pin and ground immediately before flashing.

The USB ports on these are a little fragile. If it will be used in a situation where there is any potential for strain on the port, I would recommend going for one of the brands with a reinforced port. Hopefully the manufacturer considers reinforcing it in future.However, the seller / manufacturer was quick to refund me the value of the board that failed. Great customer service.

As others have mentioned, these have particularly weak USB connectors on them. I figured people were abusing them, and got these anyway: those USB micro connectors can get pulled off if you're really rough on them. The connector could be strong, but it seems like an inadequate amount of solder paste was put down, making them mechanically weak. You can tell that's part of the problem because they break off cleanly, without pulling up pads. I was able to reattach mine after adding an appropriate amount of solder paste, and then reinforced it with a "seat belt" of hot glue going up and over the connector.Aside from the factory trying to save a few dollars over the full run of these, they are actually pretty great. It's really disappointing that they did a bad job on the QC of the single most important part of the build.If you buy these, definitely take a minute to hot glue the connector down. I literally got about five cycles out of mine before it kinda jumped off the PCB, and it's not a fun thing to resolder.

I bought these for a volume issue I had. I needed to purchase a new keyboard but it had no volume buttons on it. I made a HID volume button from the use of one of these and already had my code ready. Plugged it in and set port, compatible board and uploaded without issue several times. Perfect product. A+++++

Got what I expected.They work, other than the one which experienced a failure of the USB connector on the second insertion.Would recommend, but make sure you have ~25% more than you need for your project!

The USB connectors on these are surface mounted and very fragile. Other (but not all) brands of pro micro use through hole mounted USB connectors which are much stronger. Of the 4 of these that I purchased, 2 of them had the connector completely break off under normal usage conditions and a third is barely hanging on. I'm not swinging them around by the USB cable or anything, just plugging them in and unplugging.