Onkyo SKW204 Bass Reflex Powered Subwoofer (Black) Measures 10-13/16 x 18-5/8 x 16-7/8 inches Auto standby/on circuitry Crossover control and a phase invert switch let you fine-tune the bass output Powered subwoofer for your 5.1- or 7.1-channel surround sound system 230 watts of power; 10-inch cone Powered subwoofer for your 5.1- or 7.1-channel surround sound system Crossover control and a phase invert switch let you fine-tune the bass output 230 watts of power; 10-inch cone Auto standby/on circuitry Measures 10-13/16 x 18-5/8 x 16-7/8 inches