20/10/5 watts RMS Power/70V 40/20/10 watts RMS Power/100V 250/500/1K Ohm Impedance Plastic horn,plastic cover,aluminium ring,steel bracket Sensitivity:108dB/1W,1m Frequency range:360Hz-5kHz Dimension: 205(l)X317(w)X365(h)mmBuild-in transformer