Review on SainSmart 101 70 102 8 Channel Relay Module by Casey Nzuki

I bought this relay to work with my Arduino and experiment with turning on indoor Christmas lights with music. As many have said, the documentation is limited, but there is enough information on the web to get it up and running fairly easily. I turned several electrical devices on and off for about 30 minutes. It's not the product's fault, but they are very noisy, so I had to put them in a box with soundproofing material for the purpose of "Christmas lights with music". Most relays click when switched. So when 8 of them rattle to the music it's pretty loud. My conclusion is that using it for this purpose will wear out the relay fairly quickly. If you are looking for a fast switching relay I would suggest the solid state version although they have a lower power rating. My flashlights are 120 volts so I chose mechanical ones. The product is very durable, well built and works exactly as advertised. Maybe I'll reassign this product to control other high voltage devices in the house. Based on my experience I would say that this is the ideal device for home automation projects.