Volant Universal Round Black Prefilter (Fits Filter No. 5120/ 5143)Volant's Element Armor Pre Filters are treated using a proprietary hydrophobic process that protects your filter from the elements without reducing airflow. This unique material filter out debris as tiny as road dust to protect your filter and extend maintenance intervals. Volant's Element Armor Pre Filters are reccomended for all off road or severe duty driving conditions or anyone looking to maixmize filtration life.