Note: Supports USB 2.0 high speed transmission, fully compatible with USB1.1.Flashing LED at the base of the speakers.Due to the lighting effects and shooting angles, there is color difference in the product, please understand.Due to manual measurement, there is a tolerance in the product size. Specification: Material: aluminum alloy_x000D_Product size: 5*5*5 cm_x000D_Battery: Built-in polymer battery (lithium battery) 300mAH_x000D_Output power: RMS 3W mono THD=10%_x000D_Frequency response: 150-18000Hz (3dB)_x000D_Signal-to-noise ratio: 80dB_x000D_Speaker: 1.77 inches (outer diameter 45MM) anti-magnetic, 4 ohms_x000D_LINE In interface: original line connection is required (speaker comes standard) Features: 1Made of high quality fluorescence surface aluminum alloy, elegant and stylish in appearance. 2Good sound quality lets you indulge in your favorite music. 3Support TF card, USB disk, FM, etc.. PackageList: Speaker*1Audio cable*1