SoundQubed HDS210-D2 600W RMS 2 Ohm Dual Voice Coil with 2.5" four (4) layer coil Vented back-plate for optimal gap cooling and less turbulence in the coil gap Heavy Duty push connectors for ease of install ( Accept up to 10awg speaker wire) Stamped, steel frame and black electroplated top and bottom plates for even more added cooling A rigid non-pressed cone and a high excursion foam surround