Matrix 1000 watt 10 in subwoofer High quality poly injection core Foam Surround 2" High temperature Kapton voice coils 800 watts max/400 watts RMS 50 oz magnet Concealed magnet Impedance: 4 OHM Efficiency: 89dB Frequency response: 40Hz - 2.8KHz Mounting Depth: 3-1/4"