Works as intended and very easy to use!

Easily control heat, a/c fans, and de-humidifier with this 4 port relay board. Upgraded my Arduino weather station to a full HVAC control system.

I wired this to an RF receiver from adafruit and some household AC sockets and gave it as a gift. Now the recipient has 4 individually toggled remotely controlled AC sockets.

I think SainSmart is really a fair-price online shop. They offer many varieties and selection of Arduino tools, one-stop shop make me more convenient to find tools for my project, Yeah, it is pretty good.

Have used it for several days. Smooth operation and no problem were found. Not bad!

I think SainSmart is really a fair-price online shop. They offer many varieties and selection of Arduino tools, one-stop shop make me more convenient to find tools for my project, Yeah, it is pretty good.

it's a nice relay board for my arduino projects. Good product an unbeatable price, I will buy the next time if needed.

Got my order in exactly 2 weeks, quicker then I expected coming from China to Canada. Had it up and running within minutes, took longer to strip the wire then it did to hook it up and write the code. The only thing that I had to search for was what the VCC-JDVCC jumper did. If you remove the jumper you can use a separate power supply to run the relays if you hook it up to JDVCC. With the jumper in place the power for the relays comes from VCC aka your arduino.

I watch at Amazon a video customer review about this relay module. I thought it was great so I bought one here. It is well made and it works as it should