DAOKI 5 Pcs KY-019 5V 1 Channel Relay Module Board Shield for PIC AVR DSP ARM Arduino with Dupont Cable, 24AWG Wire

The control signal DC or AC. 220V AC load can be controlled.
Transistor drive to increase the relay coil control pins high impedance.
The control pin has a pull-down circuit to prevent malfunction relay vacant
Size: 26 x 34mm / 1.0 x 1.32"
Widely used for microcontroller development board module can be used as home appliance control