Alpine SWA-12S4 BassLine Series 12" 4-ohm Subwoofer Max RMS Power Capacity: 350W Peak Power Capacity: 1000W Frequency Response: 30 Hz-200 Hz Diaphram Material: Reinforced Parabolic Cone Structure with Poly-Mica Dust Cap & Pulp-Kevlar Cone Body and 2-Piece Structural Parabolic Design Power Range: 150 W-350 W RMS (efficace)