Audiobahn 15-Inch Dual 4 ohm Natural Sound Series Car Subwoofer (AW1571J) 15 inch High Excursion Series Subwoofer Power Handling RMS: 500 watts Impedance: Dual 4 ohm High gloss high-strength carbon composite cone with laminated pulp reinforcement Tall narrow foam surround increases cone surface area which means more air displacement