Monster THX SL200-SW BK Select Certified Powered Subwoofer (Piano Black) (Discontinued by Manufacturer) Dimensions: 16.1 L x 25.3 W x 20.5 H Weight: 90 lbs. THX Select certification delivers movie theater quality sound in the comfort of your own home. Curvilinear enclosure cancels standing waves for clear imaging and a deeper, more precise soundstage. 24k gold-contact RCA connectors and binding posts for maximum signal transfer and connection flexibility. 12" magnetically shielded woofer is driven by a powerful 200 Watt amplifier for clean, tight bass.