The Pre-Oiled Air filter - Yamaha/Fantic YZF250 2019-2023, YZF450 2018-2022, WRF/YZF-X 250 2020-2024, WRF/YZF-X 450 2019-2023, XXF/XEF250 2021-2024 PF 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.. "Twin Air filters are slightly smaller than stock filters to increase air space around the filter and improve circulation. The resulting increase in air volume around the filter improves circulation within the airbox. 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.. Features:Coarse open-pore foam catches airborne dirt, grime and sand. Fine open-pore inner foam acts as a second filter to trap the smallest particles while ensuring maximum air passage. Exclusively formulated adhesive withstands repeated cleanings, even with harsh solvents or gasoline. Thick, flat foam, greaseless sealing ring ensures maximum contact with your airbox, while acting as a breathable gasket for increased air passage. Fused outer and inner elements prevent dirt and grime from being lodged between layers. ". Manufacturer part number: 152222FRX.