Alpine SWR-8D4 8" Car Subwoofer SWR-8D4 - Alpine 8" Dual 4-Ohm Type-R Series Subwoofer Kevlar reinforced pulp cone with HAMR Santoprene rubber surround Frequency response: 30-200 Hz Power handling: 150-350 watts RMS (175 watts per coil) | Peak power: 1,000 watts Top-mount depth: 4-1/2"