Alpine SPR-60C 6-&frac12;" 2-Way Component System Type-R 6-1/2" 2-way Component System | Power Handling: Peak: 660 watts per set / 330 watts each side | RMS: 220 watts per set / 110 watts each side Impedance: 4 ohms | Hybrid layered-pulp woofer with rubber surround 1" | Textile ring-dome tweeter External crossovers  12 dB/octave (high -pass) and 6 dB/octave (low-pass) crossover points | Frequency response: 65 Hz - 29,000 Hz Sensitivity: 88 dB | Top-mount depth: 2-3/8"