Impedance: 8 ohms Power Rating: 225W Maximum Power: Frequency Response: 50Hz-4kHz Voice Coil Diameter: 4", 101.6mm Depth: 5", 127mm Coil Construction: Aluminum voice coil Magnet Composition: Ferrite magnet Cone composition: Paper Cone Nominal Basket Diameter:12", 304.8mm Sensitivity: 100 Magnet Weight: 109 ounce Core Details: Vented core Coil Former: Polyimide former