ZXL-H3 Portable Teaching Microphone Amplifier with Time Display, Spec: Wired Version (White) 1. Material: ABS, electronic components 2. Function: insert card, radio, voice prompt, call function 3. Channel: 2.1 4. Number of speakers: 1 5. Bluetooth protocol (wireless model): 5.1 6. Effective distance: 10 meters 7. Operation mode: button 8. Play format: MP3, WMA, WAV, APE 9. Support format: TF card 10. Frequency response: 90Hz-12 Khz 11. Signal to noise ratio: 65dB 12. Loudspeaker resistance group: 2 ohms 13. Output power: 8W 14. Built-in battery: 4500mAh lithium battery 3.7V 15. Charging voltage: DC 5V 16. Charging time: 1-2 hours 17. Use time: about 15 hours 18. Transmitter battery (wireless model): button battery (delivered with battery) 19. Multifunctional loudspeaker, digital clock design, can also be used as an alarm clock 20. Two styles, two ways of use, you can choose freely 21. The smart display shows the remaining battery power and the working status is clear at a glance 22. Dimensions: 7.5 x 11.5 x 3.1 cm 23. Product weight: about 230 grams