This 8" powered subwoofer features a bottom-firing, flared port, bass reflex design for reduced port noise and increased bass response. It also utilizes a long-throw 8" woofer and up to 80 watts of power, with a frequency response of 40-140 Hz. The amplifier features high and low level inputs and high level outputs, a phase switch, independent volume control, an auto on/off switch (activated by an input signal), a variable 12 dB electronic low pass filter and crossover frequency control. This compact subwoofer is 12.75" H x 12.19" W x 14.375" D and finished in a black vinyl.