Feature:1. Built-in 3.7V 300mAh rechargeable lithium battery, support up to 8 hours of working time2. The red LED indicator indicates that the device is charging, and the green LED indicator lights up to indicate that the device is fully charged. Two indicator lights indicate that the device is fully charged, and one LED indicator means less than 75 percent remaining power3. Headphone mini plug amplifier with distortion effect. Just plug music into the guitar, you can enjoy music at home or outdoors4. Function knob can control tone, distortion, volume adjustment. The AUX in the jack allows you to use it with a mobile phone or MP3 player. There is a 3.5 mm headphone jack5. The design is small and easy to carry. You can put in your pocket when you are out, plug and play. No matter where you go, you can play the guitar freely anytimeSpecification:Item Type: Plug AmpMaterial: ABS and electronicsBattery Type: 3.7V 300mAh rechargeable lithium batteryHeadphone Jack: Approx. 3.5mm or 0.1inSize: Approx. 8.3 x 7.9 x 2.8cm or 3.3 x 3.1 x 1.1in.Package List:1 x Plug Amp1 x USB Charging Cable1 x Audio Cable