Mount the Mounting Rails. (Follow this link to find out how)
There are hooks on both Mounting Rails, which should be facing inwards of the network rack. This hook will hold your PATCHBOX/Frame.
To achieve that, carefully guide and slide in your PATCHBOX/Frame. The hook of the Mounting Rails needs to be hooked in the cutout provided for this purpose.
The threads of the Mounting Rails should be put in the holes of the ears of the Frame. Now, add the Patchcatch on both sides between the rail and the Frame (you can find an instruction here) and take the hex nuts and fasten them.