The Rockford Fosgate Crossover coil is a vintage and rare piece designed for their Sub Woofer 6.6 model. This single voice coil is a key component in the car audio system, providing high-quality sound and performance. With the Rockford Fosgate brand known for producing top-line audio products, this crossover coil is a sought-after item for car audio enthusiasts looking to enhance their vehicle's sound system with a touch of nostalgia and exclusivity.