This  AZ-Delivery 4 relay module  consists of four LEDs, four resistors, four NPN transistors, four diodes and four relays that can handle up to 5A 50V AC.

The relays are generously sized, but still compact, to enable continuous operation even under unfavorable operating conditions. Using an additional transistor, the module can be switched quickly and easily with various low-power microcontrollers.

The optocouplers and diodes protect your controller from damage. The power source can be configured using a jumper on the board.