Alpine Type-S SWS-12D4 12" Inch 1500 Watt Subwoofer WIth Massive Dual 4-Ohm Voice Coils, Fourth-Generation, More Bass In Less Space Features: Alpine Type-S SWS-12D4 12" Subwoofer Peak Power Output: 1,500 watts RMS Power Output: 500 Watts Dual 4-Ohm Voice Coils Built Like Type-R Massive Voice Coils High Strength Steel Frame Concealed Mount Gasket System High-Grade Strontium Ferrite Magnets More Bass In Less Space Alpine"s Patented Airflow Management System Keep it Cool 8 AWG Push Terminals Kevlar Reinforced Pulp Cone HAMRS Santoprene Rubber Surround Frequency Response: 26-200 Hz Sensitivity: 86.5 dB Top-Mount Depth: 5-13/16"