The RetroSound Amplified Subwoofer System is designed to fill in the low frequencies that are typically missing from your classic car, truck, SUV or van sound system. This 8 inch diameter amplified subwoofer system is contained in a compact yet rugged cast enclosure that is only 2.75 inches tall, making it ideal for installation underneath or behind your seat. With plenty of built in features, including a class D digital amplifier, a remote level control and a variable crossover control, you can deliver the right amount of deep pounding power when you want it.