Pair of SD-2 8 D4 - Sundown Audio 8" 300W RMS Dual 4-Ohms Subwoofer SD28D4 Power : 300 RMS Depth : 4.75" Suggested Box : 0.25 ft^3 sealed Re : 6.03 ohms (series) Sens 1w/1m : 82.29 dB