The Rocktron RMM900 MIDI Cable transfers MIDI commands from your MIDI footcontroller (with 7-PIN MIDI Out Jack) to any MIDI-controllable gear with 7-Pin MIDI input. Carries A/C power to your footcontroller. Plug either end of the 7-Pin MIDI cable into a MIDI input jack and the other end into the output of your MIDI footcontroller. Plug your footcontroller"s A/C adaptor into the receptacle on the back of your preamp, amplifier or effects unit marked "phantom power". (Pins 6 and 7 of the MIDI cable will transfer power to your footcontroller). 30 foot length (900 cm)