ANOTHER OPTIONAL I/O LOCATION
Through a few simple steps, the I/O module can be moved from the bottom of the case to the top, which creates the 4th optional I/O placement location.
By taking out the I/O cables from the I/O module box, they can be relocated in the top I/O kit. Please note that the audio/mic port needs to be placed towards the front of the case.
Source : Lian Li O11D EVO Top IO Kit