This is a multi-function guitar effects system with a built-in USB audio interface and stereo speakers. **Key Features:** * Built-in COSM amp modeling and a variety of effects * USB audio interface function (supports 24bit/96kHz) * Built-in stereo speakers * Guitar/bass input, as well as microphone input and AUX input * MIDI IN/OUT terminals **Included:** * Main unit (GS-10) * Genuine AC adapter *Please note: Instruction manual, original box, USB cable, and software CD-ROM are not included.* The instruction manual and USB drivers will be downloaded and included on a USB drive. I have confirmed the following: 1) Replaced the batteries with new ones. 2) Reset the settings to factory default. 3) Connected a guitar and confirmed sound output. 4) Connected a microphone and confirmed sound output. 5) Adjusted various knobs and confirmed changes in sound. 6) MIDI connection has not been tested. This is a simple check, but I don't seem to be able to fully utilize it due to my lack of knowledge, so I am putting it up for sale. It is an older item, so please understand this before purchasing. Thank you.