?The S&S® air cleaner kit for Indian® touring models with Thunderstroke 111 engines not only looks great but can provide an increase of 5 hp when paired with performance mufflers and tuning. ?? The high quality, washable cotton gauze filter high flow air filter doubles the filter surface area, resulting in a 37% increase in airflow. Engineered to maintain leg clearance, and CNC machined from billet aluminum for greater durability.