3.5″ Particulate Filter Back System Raw 409 Stainless Steel Features Raw 409 stainless steel 3.5″ particulate filter back Specification Part No: E4FR04PFB Vehicle Model: RANGER Diameter [in]: 3.5 Material: 409 Stainless Steel Important Information: Image is not of actual product - Image coming soon. Upgrade your Ford Ranger Raptor with this 3.5-inch stainless steel particulate filter back system. Made with raw 409 stainless steel, this system is built to last and provide your vehicle with top performance. Trust in its quality with part number E4FR04PFB and enhance your vehicle's performance.