Sundown Audio Z-15 V.5 D1 15" 2000 Watts RMS Dual 1-Ohm Z-V.5 Series Subwoofer Sundown Audio Z-15 V.5 D1 Car Subwoofer | Power Handling: RMS: 2000 Watts | Voice coil configuration: Dual 1 Ohm | Xmax = 35mm one-way by 70% BL | Heavily vented magnetic gap Spring Loaded Terminals | Optimized high-velocity pole vent | Innovative high-velocity vented frame spacer ring | Black aluminum 3 inch 4-layer voice coil Mega-Roll v.2 surround | Custom tooled six spoke basket | Large aluminum Faraday (shorting) Ring | Stitched-On Double-XL Tinsel Leads to prevent fatigue and failure Top Mount Depth: 11.99" | Recommended Ported Box: 4.25 cubic ft. | Woofer Displacement: 0.25 cubic ft. | Outside Diameter: 15.51" Cutout Diameter: 13.83" | Recommended Tuning Frequency: 32hz | Recommended Port Area: 68 in^2