Polk Audio PSW505 12-Inch Powered Subwoofer (Single, Black)

Single powered subwoofer in black for use with stereo or home theater speaker systems
Equipped with one magnetically shielded 12-inch long-throw woofer
Slot-load venting minimizes turbulence, noise, and distortion
Rated to 300 watts of continuous power (460W peak)
Measures 16-1/8 x 15-1/8 x 18-3/16 inches (HxWxD)