Using this nylon prefilter is easy. First, make sure you have removed your carb intake air filter (which is sold separately). Then, place the prefilter over the top of the air filter. When cleaning, gently wash the prefilter with mild soap and water, and let it dry completely before re - using. Keep it away from sharp objects to avoid damage. Check it regularly for dirt and debris, and replace it when it becomes too dirty to ensure your air filter works at its best.