5.25-Inch 180 Watts Coaxial Speaker System with additional voice coil ventilation for increased power handling and EXP pole core technology for maximum excursion and lower harmonic distortion. General: Cone Material: Injected PP. Surround: Rubber Tweeter: PEI Neodymium Magnet Frequency Response: 70-20,000 Hz. Sensitivity: 91dB. Mounting Depth: 48mm. Diameter: 130mm. Impedance: 4 Ohms Designer grilles