Specification : - Power 900 WATT 1800 WATT - Maximal Power - Nominal Diameter 390 MM - Rated Impedance 8 OHM -Sensitivity (1 w/1m) 95dB - Frequency Range 40-2000 Hz - Voice Coil Diameter 99.5 MM - Magnet Diameter 220 MM -Resonance Frequency Fs 40 Hz - Total Factor Qts 0.89 -Effective Moving Mass Mms 110 GR - Equivalent Cas air load Vas 140 Liters - Waterproof Fibre Cone 8.50 KG - Nett Weight - Gross Weight 9.45 KG - Packing Size 41*41*20 CM