This is a Geek Squad Certified Open Box Product. See below for more information. Take your home theatre experience up a notch with the Sony SACS9 115W subwoofer. Designed with a built-in amp, 250mm cone diaphragm, and Mica Reinforced Cellular woofer, this subwoofer pumps out tight, authentic bass. The carefully crafted design minimizes distortion and cabinet vibration to keep sound pure.