Amplified HI-FI Speaker Multimedia SystemPerformance SpecificationMagnetically ShieldedBuild-in AmplifierDrive Unit :21/4" SpeakerFrequency Range : 60hz-20khzImpedance :4wT.H.D:Under 0.05%Input Sensitivity :200mv-1.2vDimension (w*h*d):190*104*186mmcolor box size:152*90*165mm (40pcs)cartoon box size:470*316*676mm0.1cube every cartoon box