Alpine SWT-10S4 10" Subwoofer (4Ω) General Features: 10" SWT Series Single 4-ohm Shallow Mount Truck Subwoofer Power Handling: Peak: 1,000 watts RMS: 350 watts Recommended Power Range: 100W - 350W Poly-Mica Dust Cap & Pulp-Kevlar Polyurethane Foam Surround H.A.M.R. Surround Technology Spiral Cut Aluminum Former 65mm Voice Coil with High-Temp 4-Layer SVC Winding 8AWG Push Terminals Top-mount depth: 4-3/16" Mounting Diameter: 8-15/16'' Frequency Response: 30 - 200 Hz Sensitivity: 84.8 dB