The M-Audio USB Uno is a small and simple USB MIDI interface. It offers basic 1 x 1 operation bus-powered mobility and comes with its own built-in USB and MIDI cables. Features 1-in/1-out MIDI interface 16 MIDI input channels 16 MIDI output channels Bus-powered?requires no external power supply Extremely compact and lightweight for mobile or desktop use Built-in USB and MIDI cables Specifications Size/weight: 3-1/2″ (w) x 7/8″ (h) x 1-13/16″ (d) x 116″ (cable); .075 lbs. Requirements Compatibility MME Mac OS X Core MIDI Minimum System Requirements (PC) Windows 98SE / Me / 2000 (SP4) / XP (SP2)* / Vista (32 bit) Home and Professional Edition only. Windows Media Center Edition is not supported. Minimum System Requirements (Mac) OS X 10.1.5 10.2.8 10.3.6 10.4 10.5.1