Professional subwoofer 551 mm (21"), cloth edge, paper cone.- RMS power output: 1200 watt- Impedance: 4 Ohm- Sensitivity: 98 dB- Frequency response: 35-1500 Hz- Magnet weight: 201 oz- Voice coil diameter: 114 mm- Recessed diameter: 511 mm- Mounting depth: 237 mm