Magnetically Shielded Build-in : Amplifier Drive : Unit:2"*2 SpeakerRMS: 2W,(P.M.P.O:480W) Frequency Range:60Hz-20KHz Impedance:4 T.H.D:Under0.05% Input Sensitivity:200m V-1.2V Packing Details: 285*172*276 WEIGHT:2.5KG 20 CONTAINER:1400PCS SPEAKER :SIZE(mm): 210*105*115