ESI M4U eX 8-port USB 3.0 MIDI interface with USB hubHigh Performance USB 3. 0 MIDI with automatic I O detectionM4U eX is a compact and yet extremely powerful USB 3. 0 MIDI interface with 8 MIDI ports. Each of the 8 ports can either be used as a MIDI input or as a MIDI output, replacing not only traditional MIDI interfaces like it's popular predecessor models with 4 inputs and 4 outputs, but providing also other possible configurations. For instance, you can use up to 8 outputs at a time or up to 8