1. Plug: 2 round 5-pin plugs of MIDI IN/ OUT, which respectivey connect to the ports of "MIDI OUT" and "MIDI IN" of the electronic musical instruments2. Cable Length: approx. 1.8 m3. compatible with the operating systems of XP, VISTA, OSX, etc.4. Operating steps: 1) Connect the cable marked "IN" to the MIDI "OUT" socket of a MIDI keyboard (or MIDI device)Connect the cable marked "OUT" to the MIDI "IN" socket of a MIDI keyboard (or MIDI device) Plug the USB cable into any free USB socket on your computer 2) With the USB MIDI cable, you'll be able to compose music on PC by simply connecting your PC to MIDI input equipment, and MIDI keyboard can be powered