HCDC RPi GPIO Status LED & Terminal Block Breakout Board HAT for Raspberry Pi A+ 3A+ B+ 2B 3B 3B+ 4B

Since Amazon likes to combine reviews for totally different products, this review is for the HCDC RPi GPIO Status LED & Terminal Block Breakout Board HAT. I'm not sure why people complained about putting this board in a case. It is pretty obvious that many HATs will not fit inside a closed case. This board will work with a male to female 40-pin flat extender cable if you remove the two plastic posts on either side of the connector. You really don't need those posts except to permanently attach it to the base board or another HAT. The connector works pretty well as a "foot" and you can leave the other posts for feet on the other side. I am using a Compute Module 4 with a WaveShare IO baseboard. This has plenty of clearance above the Waveshare heat sink and Compute Module 4. Although I can't close the case, I could file a slot in the cover and use a ribbon cable. My only minor complaint is that the signal designations on the terminal blocks are ordered differently than for the connector pins. I haven't figured out if there is a system to it, but they seem quite random. In some cases the label is the GPIO pin and in some cases it is the usual function, like "TX' or "RX". Probably it wasn't possible (or easy) to make a layout on the terminal blocks to match the connector pin ordering. With a little bit of care in finding the right connection, this provides all the signals. What impressed me was the construction. If this is built by hand, it was done very well. There were no cold solder joints, splashes or burnt lands from using too much heat. It actually looks like it was put through a wave soldering or surface mount soldering machine. The plastic posts could have been metal, but they're good enough being plastic. For the price, this board is a good value. I'm porting an OS to the Compute Module 4, and this board has saved me from hanging LEDs off of my board. It is also nice to see the serial port TX and RX data to at least know of the signals are reversed (one LED on instead of 2).

Way better than using the pins

This is an excellent little GPIO breakout board you can attach to your pi 4. Arrived fast. Packaged okay.. to be honest the packaging was all torn up and I was surprised it wasn't broken in shipping but it worked. It's hard to actually damage an item like this I think unless you overdrive it. I attached it to my pi and an Adafruit 240x240 LCD display then wrote a matrix style screen saver in python and it works flawlessly. I think I read it had led's in the amazon description, but seeing it's leds light up looks great and is actually educational. I bought this one for my pi 4 dev machine and am so impressed I will likely buy a couple more for other pi 4s I use in python automation code development. I couldn't be happier with purchase. Highly recommend if you're into things like this.

I used this breakout board in my Raspberry Pi–based oven controller, and it made wiring and debugging way easier. The screw terminals keep connections secure and clean, and the LED indicators on each GPIO pin are incredibly helpful for monitoring pin state at a glance—no more guessing if your code or wiring is working. It plugs directly onto the Pi's GPIO header and includes clear pin labels, so setup was fast and error-free. Perfect for permanent installs or prototyping where reliability and visibility matter. Highly recommend for any Raspberry Pi GPIO project—especially if you’re driving relays, sensors, or building something like a custom control panel. This board makes it way easier to troubleshoot and maintain.

5 star product but those included PCB spasers are trash. Rigged my HAT to Pi4 with long M3 screws. I know they should be M2,5 but this way the grip is better. Anyway, breakout board itself is what it needs to be. Recommended to all who like to play with GP pins. If you plan to put this combo in a case, please make sure that you can fit these in before purchase. It's not all about the case measurements but also assembly.