DNA Air Filters - Air Filter for Harley Davidson XG 500 STREET 15-16 / XG 750 STREET 15-20This filter features DNA's advanced FCd (Full Contour design). Installation of the filter is very easy, simply follow the information that can be found in the Harley Davidson workshop manual. The filtering efficiency is extremely high at 98 99% filtering efficiency (ISO 5011), with 4 layers of DNA Cotton. The flow of this DNA Fcd filter is high, 196. 96% more than the Harley Davidson stock paper filter! DNA Fcd air filter flow: 137. 30 CFM (Cubic feet