Endorphin.es Shuttle Mate (MIDI + USB-MIDI -> one MIDI + USB MIDI)

Shuttle Mate
6 HP width, up to 1 1/3“ in depth
merge MIDI and USB-MIDI streams into one MIDI/USB MIDI flow
perfect mate for Shuttle Control to be able to connect a few MIDI devices into Shuttles ‚to host‘ input (e.g., merge drum machine‘s MIDI clock while playing with your MIDI controller)
no bus power required – device runs fully on power delivered from USB socket, however it also may be powered from the bus board

Manual