MB Quart PWM304 Premium Vehicle Dual 4-Ohm Voice Coil Subwoofer, 500-Watt 12-Inch Two tone woven glass fiber cone and dust cap. 2.5&#34; high-temp voice coil. Fuse Protected Selectable, Parallel/Series impedance terminal. Dual mirror image treated spiders. 12&#34; DVC 4 ohm subwoofer 500 watts RMS 1000 watts MAXX