Amazing bass in a compact package! The one-of-a-kind Tang Band W5-1138SMF 5-1/4" subwoofer has a generous 9.25 mm of Xmax. A wide roll surround, raised flat spider, and large 1-1/4" 4-layer voice coil ensure impressive bass performance and high power handling. The vented pole and vented spider allow good airflow around the coil to improve heat dissipation and reduce power compression. The ultimate miniature subwoofer driver!