The Twin Air Pre-Oiled PowerFlow Air Filter is a great way to boost the horsepower and performance of your motorcycle. Twin Air designed their Pre-Oiled PowerFlow Air Filter to be used exclusively with the Twin Air PowerFlow Kit. The special backfire-resistant layer of foam laminated to the inside of the filter makes the Twin Air PowerFlow filter a quick, ready-to-install assembly. After submerging it in BIO Liquid Power Filter Oil, the PowerFlow Air Filter is massaged to ensure all pores are evenly coated with oil, it's placed in a temperature-controlled room to allow the oil to completely cure. You just open the re-sealable bag and install. The original PowerFlow Air Filter completely coated in Twin Air's BIO Liquid Power Filter Oil. Comes in a new, re-sealable bag for added convenience. Filter ONLY for use with Twin Air PowerFlow kits.