The Grove - 2-Channel SPDT Relay has two single pole - double throw (SPDT) switches. It only requires low-voltage and low current signals to control the switches, specifically, you can use 5V DC to control max 250V AC or 110V DC.
The best thing is about this relay is that you can control the two channels separately. It is so convenient and reliable that it can be applied to large scale products or projects which need to switch high voltage/high current devices.
Some applications of this relay are: