You can connect the screens with each other using the cable that is included. This is a cable with a plug on each side, with this image and sound are transferred from screen A (provided with DVD player) to screen B.
The example below concerns the MES-403. It is possible that the input and output are in a different place and the numbers are not correct, but the method is the same.
In screen A you use the output with no. 4 and with screen B you use the input with no. 17.