This anti-magnetic wrap is included in all PHR fuel systems. The purpose is to eliminate magnetic interference between dual pumps running while in contact with each other as typical in dual-pump fuel systems. It also provides some vibration resistance while pumps are in contact with each other. This proprietary material is completely chemical-proof and can survive submerged in gasoline for years. Its the ONLY material that can survive inside your fuel tank and not deteriorate over time. Standard size is 3" x 6", other sizes available as required.