12cm main screen LED Digital Speaker is compact and user-friendly.  It has so good sound quality that you can indulge yourself in your favorite music anytime and anywhere. Nowadays, it is really cool and trendy to enjoy music with this multi-functional stereo digital speaker with TF Card and U Disk.  Specification: Output Power: 3W Frequency Response: 100HZ-20KHZ+-1db Speaker Size: 40mm Output Impedance: 4ohm Sensitivity: 85DB SNR:>=86db Distortion:<=0.5% Using Power: 5V/500Ma FM: 87.5MHZ-108MHZ Charging Time: 2-3 hours Using Time: 10-40 hours Item Size: Approx. 11.2 * 7 * 2.5cm / 4.40 * 2.76 * 0.98in Item Weight: Approx. 205g / 7.21oz Package Size: Approx. 14.3 * 7.8 * 3.5cm / 5.63 * 3.07in Package Weight: Approx. 245g / 8.63oz Package List: 1 * FM Radio 1 * Charging Cable  1 * User Manual