Great price, easy to use

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.