Nominal Diameter 305 (12) mm (in) Nominal Impedance 4 or 8 Ohm Magnet Weight 50 OZ (156x80x20mm) RMS Power Rating 350 Watts Program Power 800 Watts Sensitivity (1W/1m) 101dB SPL Frequency Range 60Hz - 2kHz Voice Coil Diameter 4 inch / 100mm Voice Coil Material Aluminum Former Material Fibreglass Basket Material Cast Aluminium Cone Material Paper,Carbon Fiber Surround Material Cloth