By the way, there are only three foam filter treatments that we recommend for use on the Unifilters...and none are even Unifilters own oil treatment. They are Bel-Ray, then the two Maxima's which are FFT and Fab-1. I use the Fab-1. Even these have to have the excess removed from the inside surface with paper towel as some atomize-ation plants some onto the temp/airflow sensors if the access isn't removed. Not a big deal, just means you will have to clean them from time to time.