<b> X-8 V.3 D2 | Sundown Audio 800W RMS X-8 Series Subwoofer</b> <p> <b>FEATURES:</b><br> <p> <b>SPECIFICATIONS:</b><br> <p>*RE (Ohms): 4.0 <p>*FS (Hz): 46.770 <p>*VAS (L): 4.190 <p>*Qes: 0.544 <p>*Qms: 4.432 <p>*Qts: 0.485 <p>*Le (mH): 2.01 <p>*BL (NA): 18.508 <p>*Mms (Grams): 158.641 <p>*Cms (uM / N): 72.995 <p>*Sens (dB @ 1w / 1m): 81.8db <p> <b>Enclosure Recommendations :</b><br> <p>*Sealed Enclosure: Not Recommended <p>*Ported Enclosure: 0.75-1.0 cu ft <p>*Recommended Tuning: 32Hz <p>*Recommended Port Area: 12 - 16 sq in <p>*Displacement: 0.13 cu ft <p>*Depth 7.00" <p>*Outside Diameter: 8.70" <p>*Cut-Out: 7.36"