Specifically designed for modern 4-stroke applications, 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. 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, 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 "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 " AIR FILTER - FIRE RESISTANT FOR POWERFLOW KIT 152222C FANTIC XXF250 21-24 XXF450 21-23 XXE250 21-24 XXE450 21-24 YAMAHA YZ250F 19-23 YZ450F 18-22 YZ250FX 20-24 YZ450FX 19-23 WR250F 20-24 WR450F 19-23