Fangrui Product Details 1. White Noise Bone Conduction Bluetooth Speaker Sleep Instrument 2. Material: Abs+pc Plastic Shell 3. Speaker: 8 Ohm2w 4. Frequency Response: 20hz-20khz 5. Bluetooth Version: 5.2 6. Decoding Method: Tf Card (mp3wmaflacapewav), Bluetooth (sbc) 7. Tf Card Capacity: 32g (max) 8. Operating Distance: About 10 Meters 9. Normal Working Hours: Play Music For 15 Hours 10. Prompt Voice: English 11. Led Lights: Red And Blue Status Indicator Lights 12. Operation Mode: Multi-function Compound Key 13. Battery Capacity: 500mah3.7v 14. Charging Interface: Type-c 15. Charging Time: 2 Hours 16. Charging Current: Dc5v310ma 17. Charging Voltage: 5v 18. Place It Under The Pillow And Sing Softly At 360 Degrees 19. 30 Minutes60 Minutes Free Setting Time And Automatic Shutdown 20. Dual Speakers Diffuse Sound, 3d Surround Sound Effect 21. Type-c Charging Interface, Fully Charged In 2 Hours 22. Overcharge Protection, Slow Power Consumption 23. Dimensions: 89.4x59.3x12mm 24. Weight: 48.7 Grams