Highly recommended in dirty environments. Keep your Ram-Air Filter protected from large debris, bugs, mud, etc…Banks hydrophobic pre-filters use uniform micron openings to keep your Ram-Air intake filter element clear from dust and large debris while repelling moisture. Cold and Heat resistant up to 400 degree. Banks pre-filter wraps are designed to work with your Ram-Air intake system and are constructed from a polyester mesh with uniform micron openings. It improves the filtering of larger debris and dirt by preventing them from getting embedded into the filter. This allows your your Banks Ram-Air to breathe easier for longer by increasing the time between services. Its hydrophobic surface has been treated to repel water and improve performance in humid or wet environments. The pre-filter is able to resist heat up to 400 degrees Fahrenheit and will not shatter in freezing temperatures.