For JOYO guitar effects are the mildest of the three distortion guitar effect types, producing warmer overtones at quieter volumes and can achieve a harsher distortion as gain is increased. Smooth-simply exquisite, also nice sustain. About volume boost, introducing warm overtones when used as a clean volume boost, searing tone as well as warmth of a classic overdriven tube amp. Power:6F22 9V Battery/DC 9V adapter (not included)(When connecting the adapter, battery power would be cut off automatically) Type:JF-32 Colour:As Shown Material:Plastic+Metal Package Contents: 1 * Electric guitar effects processor 1 * English manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.