1.Pocket design, convenient to carry 2.Catch the feeling of hi-gain tone of metal sound through the headphone 3.Plug the CD or MP3 player in and play along 4.Easy to use, catch your inspiration anytime 5.Power indicator 6.Gain, tone, volume adjustment 7.Powered by 2pc AAA batteries(included) Specifications: 1.MP3 input jack: 3.5mm 2.Earphone input jack: 3.5mm 3.Weight: 55g Package includes: 1 x JOYO JA-03 Metal Sound Amp Mini Guitar Amplifier Silver