BMC Air Filters provide better air flow than stock air filters with larger cotton gauze links BMC uses several layers of oil soaked cotton allows to block any impurity larger than 7 microns Wider filtering area Greater retention and screening: BMC air filters scored an impressive 97.5% filtration efficiency at ISO5011 test Maximum air permeability and higher air flow passage The choice of champions BMC equips some of the most important teams in MotoGP, WorldSBK and Formula 1 racing