Midiman USB Midisport 2x4 Not Factory Sealed (Midi Interfaces)
This compact multi-port MIDI interface for USB-equipped PC and Mac computers is bus-powered, making it perfect for use with laptops. Two separate 16-channel input ports allow systems to accept up to 32 discrete MIDI input channels, while four individual 16-channel output ports can address up to 64 discrete MIDI output channels.

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