... 2.ce,fcc 3.OEM&ODM service wireless air bass bluetooth mini speaker *Bluetooth version: VER2 ... in 5 v booster circuit supply power amplifier,to guarantee the lithium battery in voltage change, ... change* Innovative horn paper cone embossing process, to increase the diaphragm area, and strengthen the bass ... shockproof bottom pad, when dirty or low viscosity, may directly clean it with water* AUX (Line IN) ...