Pioneer TS-WX306T bass reflex subwoofer 12" (300 mm).

Pioneer TS-WX306T (TS-W series) subwoofer in vented box (bass reflex) 12" (300 mm).
 
With a massive power of 1300W you'll get that fantastic undistorted sound you've always wanted in your car. 
The TS-WX305T houses a durable woofer that is built with an extended aluminium voice coil with enlarged diameter for heat dissipation and durability, and Pioneer’s patented lightweight IMPP composite seamless cone to maintain reliable power handling. 
The subwoofer has a reinforced cone body, large double stacked magnets and an extended, vented pole yoke, delivering a vast improvement in linearity. 
Wiring and installation is made easier with one-sided terminals. The sub comes in a cylindrical design to get rid of standing waves inside the enclosure in order to avoid deterioration of the bass performance.