Aem new line of filter minder gauges, takes the guesswork out of knowing if its time to service your air filter. aem new filter minder gauges are an air filter service indicator. they constantly monitor airflow and the gradual increase of air filter restriction. as an air filter becomes dirty it holds much of the dirt and debris that was kept out of your engine. with this additional dirt and debris in the way the air filter gets restricted. the filter minder gauge senses this restriction. its needle displays the current condition of your air filter. when the air filter is clean and has little restriction, the needle will stay in the green section of the gauge. as the air filter moves through its service interval it will move into the yellow section. once the filter minder needle reaches the red zone its time to service your filter and reset the filter minder gauge. aem currently has three filter minder gauges available. the dash mounted filter minder gauge (part 30-5110) is designed for mounting inside the cabin of your vehicle. the dash mounted gauge includes all the necessary hardware for mounting. ten feet of vacuum hose and bezels in silver and black are included so the gauge can be customized to match the interior of your vehicle.