Cerwin-Vega HS122D Hed Dvc Shallow Subwoofer (12", 2ohm) Dual Voice Coil Stamped-steel Slim-mount Frame With Encapsulated Motor Vented Motor Structure For Optimal Thermal Heat Dissipation Polycotton Spider With Spaced, Woven-in Tinsel Wires Oversized Parabolic Dust cap For Extreme Rigidity