"This unit condenses the functions required of an acoustic guitar processor into one device. The only equipment you need to bring to a live venue is your guitar and the A3. That's all." While the original box is not included, the unit itself is in very clean condition. There are no operational issues. It has balanced input and output, and remarkably, the same effects can be applied to vocals, making it invaluable for solo performances. You can apply Zoom's high-quality echo to both guitar and vocals. It also has a handy anti-feedback switch. Due to its limited availability, the used market price seems to be increasing. If you're interested, please consider it. Product Description: 40 Acoustic Effects It has 16 body types and 28 model types pre-set, simulating the diverse acoustic characteristics of acoustic guitars based on their body shape and materials. By selecting the body and model that matches your guitar, you can deliver the beautiful and rich sound of an acoustic guitar to the audience at a live venue. Anti-Feedback Function If feedback (howling) occurs during a performance, don't hesitate to press the ANTIFEEDBACK switch. It automatically detects the frequency causing the feedback and cuts only that band with a sharp filter. If feedback occurs at another frequency, simply press the footswitch again. It can handle up to 3 different feedback frequencies. It quickly and effectively removes feedback, which often occurs in live acoustic guitar performances, while minimizing changes in sound quality."