SainSmart 4 channel Signal Relay Module Board,For Arduino UNO MEGA 2560 R3 1280 3D Printing, Arduino

I use this in a remote controlled preamp. Each relay provides one stereo switch. Easy to drive from an Arduino. The only thing that's not ideal is that it powers up in a random state, but I think that's more down to how it's controlled, and not a flaw in

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