DNA Yamaha YZ450, YZ250, WR450 and WR250 Stage 2 Air Filter add horsepower while letting your dirtbike breathe better. The efficiency of DNA Filters maximizes breathable surface area compared to the OEM filters allowing you to get the most horsepower. The "Quick Release" is extremely useful for racing, allowing the mechanics to change the air filter in less than a minute without removing the air box. Horsepower gains are very impressive with the proper fuel recalibration.Equivalent to Yamaha OEM: 1SL144510000 TECHNICAL FEATURES Features DNA's advanced FCD (Full Contour Design) NA FCD air filter flow: Superior CFM (Cubic Feet Per Minute) @1,5" H2O corrected @ 25° Celsius The DNA filter has a 55.96% higher airflow than the Yamaha stock paper filter! Extremely high filtering efficiency of 98-99%, with 4 layers of DNA Next Generation Premium Cotton These air filters are washable and resusable Drop-In Hassle Free Installation (simply follow the information in the workshop manual) Lifetime Warranty FITS Yamaha YZ 450 F (2014-2017) Yamaha YZ 450 FX (2016-2017) Yamaha YZ 250 F (2014-2018) Yamaha YZ 250 FX (2015-2019) Yamaha WR 450 F (2016-2018) Yamaha WR 250 F (2015-2018)