This single relay module can be used in interactive projects. This module uses a high-quality SONGLE 5V relay. It can also be used to control lighting, electrical and other equipment. The modular design makes it easy to expand with Arduino boards (not included). The Relay output is by a light-emitting diode. It can be controlled through digital IO port, such as solenoid valves, lamps, motors and other high current or high voltage devices.