Autotek ATK12D4 ATK 12 inch subwoofer with dual 4 Ohm design delivers 800 watts and features heavy gauge, powder-coated, stamped steel basket. Type Subwoofer Brand Autotek Series ATK Category Mobile Condition New Color Black Subwoofer Voice Coils 2 Subwoofer Impedance (ohms) 4 Subwoofer RMS Power Handling (watts) 400 Subwoofer Peak Power Handling (watts) 800 Subwoofer Cut-Out (in) 10.94 Subwoofer Mounting Depth (in) 5.61 Subwoofer Outside Diameter (in) 12.25 Subwoofer Sensitivity (1 watt/1 meter) 86dB Subwoofer Enclosure Recommendation Small Sealed or Medium – Large Vented Subwoofer Size (in) 12 Proposition 65 Notice WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov