Item number 320643444235 on Ebay is billed as a “MidiBox 4x4”. It’s a 4-in/4-out USB-to-Midi interface. Anyone have any ideas of its provinence?
It’s a commercial MIDI interface by Tomtop made in China 
Heheh, they somehow misunderstood the concept of midi merging: “Merge function 2 ins to 4 outs included.”