Fram extra guard air filters are engineered with an advanced filter media that has been through rigorous testing and have been proven to provide 2x the engine protection than the average leading standard retail brand air filter. 12, 000 Miles change intervals helps prevent decreased acceleration and horsepower while helping improve overall performance. Fram engineering laboratories defines the air filter category by providing a clear choice over other filters. Follow recommended change intervals as noted in your vehicle's owner's manual. Based on fram group testing of filter efficiency of models ca4309, ca8755a, ca8039, ca326 and ca6479 and their standard retail brand equivalent under iso 5011.