The Relay Shield features four high-quality relays that allow for the control of high-current loads on Arduino or Seeeduino boards. It also provides a NO (Normally Open) / NC (Normally Closed) interface. This is an ideal solution for controlling devices that cannot be directly managed by Arduino's digital I/Os. The standardized shield form factor ensures a seamless connection with Arduino and compatible devices. Additionally, the shield includes four LED indicators that display the on and off status of each relay. Relays are useful for turning AC devices such as fans, lights, motors, or high-current DC drives like solenoid valves on and off.