Graph Tech Acousti-Phonic Kit - Advanced Natural acoustic sound 9-18v auxiliary power On-board controls 9-18v auxiliary power QuickSwitch Acoustic Volume with mid/dark Switch With the Graph Tech Acousti-Phonic preamp component kit, guitarists can add realistic, acoustic sound to your electric guitar, without altering your magnetic pickups You can use magnetic pickups and acoustic sounds one at a time, or blended together for an enhanced electric effect The Acousti-Phonic preamp requires a 9v battery and comes with a guitar pot for the acoustic volume (though you can also convert one of your tone pots - an included harness connects it to the ghost system) The guitar preamp kit also includes Graph Tech's popular optional switches