The Bose PS 3-2-1 Powered Subwoofer Series II is a sleek black subwoofer designed specifically for Bose speakers. It is compatible with the Bose 321 model and offers wired connectivity. This subwoofer is a perfect addition to any home audio setup, providing powerful and impactful bass for a more immersive sound experience. Tested and confirmed to be in working condition, this product is sure to enhance the overall performance of your home audio system. Few blemishes from normal use for a piece like this.