The 4″ Downpipe (FS9460) from Armor Plus is made of T409 stainless steel, making it durable and resistant to corrosion. Its key features include a 4″ diameter for improved exhaust flow and a sleek design. The downpipe is also easy to install and compatible with a variety of vehicles. Its benefits include increased horsepower and torque, improved fuel efficiency, and a deeper, more aggressive exhaust sound. Its unique selling points are its high-quality construction and performance-enhancing capabilities.