Outerwears K&N Pre-FilterRU-4720 Elevate your engine's defense with an intake pre-filter from Outerwears. Crafted from silicone-impregnated micro-mesh for water resistance and dielectrically welded at the seams, these pre-filters can capture particles as tiny as 0.005 in diameter without hindering the airflow to the engine. Featuring uniform micron-sized openings, the material allows air in while screening out sand, dirt, clay, and moisture. Features: Dyno and flow bench testing reveals no loss of horsepower or airflow when using this product Keeps your engine safer in harsh conditions Filters particles down to .005