Fangrui Product Details 1. Retekess T131s Guide Receiver Wireless Explanation Receiver 2. Note: This Is Only A Wireless Receiver, It Must Be Matched With A Transmitter (195-216mhz) To Build A Wireless Tour Guide System 3. Frequency Range: 195-216mhz 4. Channels: 49 Channels 5. Frequency Response: 50hz-18000hz 6. Operating Voltage: Dc 3.7v 7. Audio Input: 3.5mm Cable 8. Frequency Response Range: 50-18000hz 9. Signal-to-noise Ratio (snr): 80db (typical) 10. Mirror Image Rejection Ratio: Greater Than 90db 11. Distortion: Less Than 0.3 Percent 12. Effective Working Area: About 100m (open) 13. Battery Capacity: 900mah 14. Operating Time: About 20h 15. Size: About 7.3 X 4.2 X 1.2cm 16. Weight: About 45g 17. Features: 18. Portable Design, Lightweight And Compact 19. Pll Synthesis Design, High Frequency Stability 20. 49 Channels, Allowing 49 Groups To Operate Simultaneously At The Same Location 21. Built-in Rechargeable Lithium Battery, To Ensure That Can Be Used One Day 22. Lcd Display, Adjustable Volume, Power Display, Easy To Operate 23. Application: Tour Guide, Wireless Conference, Wireless Teaching, Simultaneous Interpretation, Corporate Hospitality, Factory Visits, Etc. 24. Packing List: 25. - Wireless Receiver X 1 26. - Single Earphone X 1 27. - Usb Charging Cable X 1 28. - Lanyard X 1