SONY SA-WMS815 Subwoofer.  Advanced S.A.W. Super Acoustically Loaded Woofer, 150W. Subwoofer Only for SA-VE815ED Home Theater System. Top-of-the-line powered sub with built-in 150-watt amp for impressive reproduction of Dolby Digital's low-frequency effects. Bass reflex sub with aluminum front panel, 'level' and 'mode' selector knobs. Tested works. Used, excellent condition. Small nicks per pictures. Shipped with FedEx.