The Cobalt CO104SBX is a custom vented 2 ohm enclosure containing a single 10" Cobalt subwoofer.Who knew that entry level subwoofers could perform like this... These woofers will absolutely blow your mind. With a bumped back plate, extended pole piece, large magnet, and high roll surround that give an astounding 10.25mm of Xmax. Reversible top gasket Large copper-wound Kapton voice coil Autotension push terminals Flat Conex spider with loop stitched tinsel leads Model Number CO104S Power(RMS/Peak) 200 Watts/400 Watts Fs (Hz) 39.2 Qts 0.57 Vas (cu ft) 1.080 Sensitivity 86.1db Mounting Hole Diameter (inches) 9.23 Mounting Depth (inches) 5.12