The Pre-Oiled Fire Resistant Air Filter - Kawasaki KXF250 2021-2024, KX250XC 2021-2024 For Power Flow Kit is part of the latest collection from Twin Air.. Now all customers can have the same factory service that top professional race teams and OEM customers have received for the last 10 years. Using their new state of the art filter oiling machine, each Twin Air filter is completely submerged in Bio-Oil and massaged to perfection to ensure that all pores are evenly coated. The filter is then placed in a temperature-controlled room to allow the oil to fully cure on the filter. These triple layer filters have an additional flame retardant inner layer for extra protection. Twin Air filters are slightly smaller than stock filters to increase air space around the filter and improve circulation. More air means more power for your engine. Flow bench tests have proven that Twin Air filters provide increased airflow while reducing the filters tendency to clog. The complete process provides maximum protection and maximum airflow. You just open the resealable bag and install, no mess, no fuss..Manufacturer part number: 151126FRX.