Built-in amplifier electric guitar. Sound is produced when a 9V square dry cell battery is inserted and the volume knob is pulled up. The volume knob is not original. Sound output from the built-in speaker, external output jack, and headphone jack are all good. There is no scratchy noise. Distortion is applied at the same time as the volume increases. The sound from the external output jack is clean tone. The master volume can be adjusted with the blue trim on the back cover's internal circuit board. Scratches are visible due to the item being used. The neck is generally straight. Frets are about 70% remaining. Cleaned, lemon oil applied, and strings replaced. Please purchase with the understanding that this is a used item.