Standard Efficiency Cabin Air Filters are designed to keep out dirt, soot, sand and other contaminants, while also reducing outside odors entering the cab under normal operating conditions. Cat Cabin Air Filters are designed with advanced filtration technology that reduces airborne irritants, creating a cleaner and more comfortable working environment for the operator. WARNING: This product can expose you to chemicals including Lead and lead compounds, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.