If you want to switch up to 8 high current / high voltage loads from a microcontroller, this 12V relay board can do it.
It contains 8 x 12V relays rated at 10A/250V AC (DC 30V/10A). Each relay is switched on/off by an opto-isolated digital input that can be connected directly to a microcontroller output pin. It only requires a voltage of approx 1.0V to switch the inputs on but can handle input voltages up to 12V. This makes it ideal for both 5V and 3.3V devices.
8 X 24V relays
Each relay rated at 10A / 250V
Each relay consumes approx 30mA when switched on (at 12V)