Applications: Apply to PC, mobile phone ,MP3, MP4 and FM radio etc. Frequence response: 150Hz-18KHz ... music from Micro SD,U-disk,support MP3 formatApply to PC, mobile phone ,MP3, MP4 and other audio sourceSupports FM radio ... return shipping with proper packaging.On receiving items, we will refund you immediately.Warranty &Maintenance:We provide 1 month replacement and 12 months maintenance ...