JBL Sub 100 Black 10-Inch Powered Subwoofer with High-Efficiency Class D Amplifier (Black) 10-inch (250mm) high-output woofer 100-watt RMS (200-watt dynamic) digital power amplifier Dual rear ports optimize airflow while minimizing port turbulence and audible distortion in the bass response Variable level, crossover, and phase controls Contemporary cabinet shape with angled side and top panels provide a sophisticated, modern look