This is a 5V 2-Channel Relay interface board, Be able to control various appliances, and other equipments with large current.A relay can be used to control high voltages with a low voltage by connecting it to an MCU. The 2 relays on the module are independent of each other, once a relay is triggered by the low level, the corresponding LED lights will be lit and accompanied by a crisp sound.
It can be controlled directly by Microcontroller(Arduino , Raspberry Pi, 8051, AVR, PIC, DSP, ARM, MSP430, TTL logic).