General Features: 5.25" woofer, 25mm (1") Tweeter, 75W RMS power handling (150W peak), Frequency response: 65-23kHz, Impendence: 4-ohms, Sensitivity: 91 dB/Spl, Outer diameter: 130mm, Mounting hole diameter: 120mm, Mounting depth: 56mm, Crossover included: 3.5kHz crossover frequency,ESK 130 - Hertz 5.25" 2-Way Component System