The TS-W312S4 is designed to take the “Champion” Series name to the next level with a range of improvements. With a lightweight/high rigidity cone design, dual-layer hybrid surround, large powerful motor assembly and enclosed basket structure, the new “Champion” Series sub-woofers not only look good but will perform even better! Match with Pioneer’s GM-D Series amplifiers for an impressive in-car experience! Features Pioneer TS-W312S4 - Rigid Cone Construction Combining a large rigid centre cap and lightweight high rigidity cone structure improves output performance and reduces loss. Improved dual-layer (elastic polymer & fibre) hybrid surround provides a lighter and more durable surround than traditional rubber compounds. Pioneer TSW312S4 Powerful Motor Assembly Combining a double stacked 90oz magnet (26% bigger than our previous model and some of the heaviest in its class) with a longer voice coil design, the “Champion” Series subwoofers are designed for high power handling and endurance! Pioneer Electronics Pioneer is a Japanese multinational corporation founded in 1937 that specializes in digital entertainment products. It's one of the most trusted brands in practically any field of car audio. With the renowned innovation, persistence and integrity of Japanese businesses, you can expect the latest technology and the highest possible quality from Pioneer car audio products.