... ,SD card in 4.CE,FCC,ISO,ROHS 5.suitable for multimedia room 2.0 Professional Active Speaker with USB/SD/Remote ,column ... speaker has inbuilt amplifier, you do not need another amplifier,and it is simple installation. You just hang it on whiteboard ... case with cloth cover net (we can make metal mesh speaker grille if large quantity)7.These speaker has CE,FCC,RoHS,ISO9001 ...