The DDX lineup was engineered by Skar Audio to be an SPL grade woofer that could also be utilized in daily system applications, allowing non-competitors to use the same subwoofers as those competing in the lanes. Each component used in the design of these woofers is of the highest quality for reliability and increased performance. Each Skar Audio DDX subwoofer features a massive double stack motor, 2.5 inch pure copper high temperature voice coil, and a competition grade pressed paper cone stitched to the high roll foam surround. Whether you are a competitor or just someone who wants some bass in their daily driver, the Skar Audio DDX will never let you down.