SUBWOOFER 15 " FERRITE MAGNET ALUMINIUM BASKET DRIVER FEATURES - 4 INCH COPPER VOICE COIL - 97 dB/SPL SENSITIVITY - 2000 WATT PROGRAM POWER HANDLING - FEM OPTIMIZED MOTOR AND SUSPENSIONS - OPTIMIZED COOLING SYSTEM - ALUMINIUM DEMODULATING RING - DOUBLE SILICON SPIDER - RESONANCE FREE AND HEAVY DUTY BASKET DESIGN - TRIPLE ROLL SURROUND