S17 Mini Portable Tour Guide Teaching Loudspeaker with Screen Display 1. Material: rubber paint, ABS, electronic components 2. Function: teaching, tour guide, conference, training 3. Built-in battery: 2200mAh lithium battery 4. Charging time: 3 hours 5. Use time: 20 hours 6. Standby time: 72 hours 7. Using head-mounted acoustic microphone, ergonomic design, comfortable to wear 8. Using 3-inch speakers, the volume is larger and the transmission range is wider 9. Support U diskTF card playback 10. The length of the belt can be adjusted freely 11. Dimensions: 9.4 x 8.4 x 2.8 cm 12. Weight: about 230 grams Packing list: -Speaker x 1 -Headset Microphone x 1 -Belt x 1 -Data cable x 1 Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.