Product Introduction: ① Audio head: 6.35mm audio plug which can be rotated 282 degrees and connected to guitar or other instruments ② Battery light: Display current battery level ③ Volume button: Single click volume and double click volume ④ Power switch: Turn the device on or off ⑤ Charging indicator: The indicator light is on when charging; the indicator light is off when charging is finished; the indicator light flashes when the battery is low. ⑥ Type-C interface: used for Type-C USB charging and connecting to smartphones computers etc. for recording. ⑦ Headphone port: 3.5mm headphone port Instructions for use 1. Connect the 6.35mm audio head to the guitar the headphones to the headphone port and then turn on the product. 2. Put on the headphones then play the guitar to hear the sound 21 Thank you for choosing our products. This is a headphone guitar amplifier specially designed for instrument practice. It has high-definition sound quality low latency and long battery life and is suitable for most electro-acoustic instruments. I hope it add convenience and fun to your performance practice! Color: Black Material: ABS Package Contents: 1 x Headphones Guitar Amplifier Only the above package content other products are not included. The measurement allowed error is 1-3cm.