Pre-Filters help to prevent sand, mud, and dirt, from contaminating the air filter in your 2020 Chevy/GMC 3.0L Duramax. A pre-filter is installed over your air filter and helps to extend cleaning intervals while also blocking out large debris that might otherwise damage your air filter. Pre-filters from AFE, K&N Engineering, Banks, and others are all available at XDP. Get the right pre-filter for your intake by matching up the filter dimensions, or by using the filter part number. Pre-filters are manufactured from a breathable material that lets air through while blocking large debris and contaminants.