It's a super-compact battery-powered self contained micro amp and interface for i-OS that you can use by itself, with headphones or even an external speaker cabinet this power-packed amazing little amp can drive up to a 4" x 12" guitar cab. But what makes it more versatile than any other micro amp is that it features the iRig circuitry so you can plug your i-Phone or i-Pad into it with the included TRRS cable and tap into the limitless world of Ampli-Tube guitar tone and more on your i-Phone and iPad.