4-inch, fiberglass inside/outside copper voice coil 3000W continuous program power handling 97.5 dB Sensitivity 25 Hz – 1 kHz Frequency range Dual Forced Hyperventing System Dual spider design with silicon based dampening control Triple-roll surround and corrugated straight cone geometry Incredibly linear frequency response characteristics, the highest power handling of any comparable 18-inch transducer, the lowest power compression.