- 5.25" Foamed IMPP (Injection Molded Polypropylene) Rigilite Composite Cone (Pearl White) for Higher Performance and Deeper Bass. - Butyl Rubber Surround for Smoother Response. - High Energy Strontium Magnet (Woofer & Tweeter). - Conex Damper for Linear Bass Response. - Glass-Imide Voice Coil Bobbin for High Power Handling Capabilities. - 1-1/4"" Foamed PPC (Pearl PolyCarbon) Balanced Dome Tweeter with Magnetic Fluid.