The AFE 90-50001 Air Filter Restore Kit is the perfect way to keep your Blue AFE Pro 5R media air filters clean. The kit includes an aerosol bottle of AFE blue filter oil and a spray bottle of AFE filter cleaner, so you can easily and effectively clean your filters at home. The highly refined AFE filter oil helps capture the smallest debris, making it an essential part of maintaining your air filters. It's recommended that you clean and re-oil your filters every 20-30k miles to keep them working properly.