Originally designed for our 130 Bagger GP race engine, our Race Series (RS) BA air cleaner, comes in just under an inch taller and boasts an impressive 33% increase in filter size over our standard fit BA air cleaner Impressive horsepower and torque gains on any engine and exceptional gains seen on engines running modified and/or ported cylinder heads along with intakes and larger throttle bodies The Feuling BA Air Cleaner lengthens the intake runners and increases air velocity, delivering added volume for balanced dynamic flow The one piece design, creates a clean look and eases installation when compared to the industry standard multi stack up construction Set up with OEM-style cylinder head breathing, routing into the intake with optimized vent hole locations Features a high flow velocity stack with optimal opening diameter, outer lip and internal (ID) taper High flow washable/reusable 3.335" with air filter with one piece billet cage New bolt-on air cleaner design for Harley-Davidson motorcycles Made in the U.S.A.. AIR CLNR BA RS RW/S/RD M8