Lightning Audio L2-D212 LA-Two 12-Inch 2 OHM Dual Voice Coil Subwoofer, Set of 1 L2 12" 2-Ohm Dual Voice Coil Subwoofer High modulus closed conical polypropylene cone and dust cap assembly geometry Tear and fatigue resistant poly-cotton spider High density compressed half-roll sealed poly-foam surround High temp voice coil with spun-laced Nomex insulating reinforcement collar