Marathon KVX-18SUB High Power Active 18-Inch Subwoofer System - Black Frequency Range: 37Hz - 250Hz. Maximum Sound Pressure Level: 138dB. Woofer Magnet: 62 oz. Low Frequency Driver: 3 Inch (76.2mm) Voice Coil. Crossover Frequency Adjust: 55Hz - 200Hz. Recessed Handles. Metal Grills. Dimensions: 22.04 x 22.8 x 26.8 Inch. W: 105 lbs.