Trask Assault Charge High-Flow Air Cleaner for TBW Harley-Davidson Twin CamTrask Assault Charge High Flow Air Cleaner for TBW Harley Davidson Twin Cam The air cleaner does more than house a filter. It needs to supply a large volume of clean air, and feed that air to the manifold rapidly, tumble it to prepare the air for the incoming fuel charge, all while managing engine breathing functions at the same time. For trusted performance, turn to Trask's Assault Charge. Timeless, iconic design Patented design10,876,503 B2