IDMAX12 V.4 D2 - Image Dynamics 12" 1800W Peak Dual 2-Ohm IDMAX V.4 Series Subwoofer 12" Dual 2 ohm ID MAX V.4 Series Subwoofer | Pressed paper composite cone woofer | Parabolic EPDM rubber surround | Over 2" long linear excursion | RaDiaToR cooling system for heat dissipation | Radiant Diametric Torisonal Reinforcement | High compliance suspension design | Flat spider with NOMEX cloth woven tinsel leads | High-temperature flat wire, flat wound voice coil | Inverted dust cap with logo | Powder coated alloy proprietary basket | 3-1/2" peak-to-peak surround excursion Power Handling: Peak: 1000 watts | RMS: 500 watts | Recommended Power Range: 50-500 watts Nominal Impedance (IMP): Dual 2  | DC Resistance (Re): 1.65  | Resonance Frequency (Fs): 26.51 Hz | Equivalent Volume (Vas): 77.51 L | Electrical Q Factor (Qes): 0.63 | Mechanical Q Factor (Qms): 2.96 | Total Q Factor (Qts): 0.52 | Peak Excursion (Xmax): 39 mm | Piston Area (Sd): 545.00 cm2 | Sensitivity: 85.50 dB 1w/1m Sealed Enclosure Suggestion: 1 cu.ft. | Ported Enclosure Suggestion: 1.75 cu.ft. | Displacement: 0.14 cu.ft. | Mounting Depth: 8.15 in | Outside Diameter: 12.40 in | Cutout: 11.02 in