Supports Bluetooth 5.1 connectivitySupport Bluetooth,AUX,U disk,USB,sound card inputOver-temperature and short-circuit protection against static electricityWith heat sinkVolume can be adjusted independentlyFeatures:Rich button functions, simple operation.Overheating, overcurrent, short circuit, anti-static for .APP-control, you can set a pass-word, adjust the volume of the prompt sound, switch the prompt sound, etc.Box pairing function, the wireless function enables two sets of speakers to be combined into left and right channel pair boxes, with a for STRONGER sense of spatial-positioning.Batch differences may lead to product appearance, printed text, color will be different, does not affect the use ofColor: BlackMaterial: PCB+metalPackage Contents:1 x amplifier board (need to install themselves)1 x screwdriverOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.