The S&S air cleaner kit for Indian models with the Thunderstroke engine looks great and can provide a 5 BHP increase when paired with performance mufflers and Fuel Injection tuning. The high quality, washable cotton gauze High flow air filter doubles filter area, resulting in a 37% increase in airflow. Engineered to maintain leg clearance and CNC machined from billet aluminum. Complete kits include all necessary mounting hardware.