... screen 3 rechargeable lithium battery4.FM, AUX and USB driver SV-929 usb SD card mini speaker amplifier offers a premier listening ... has digital FM radio, LED screen with frequency display and audio line-in jack for use with other portable devices, such ... headset, work as a megaphone.3. With SD card slot, USB driver, FM and line in functions4. Use reverberation technology; let ...