Twin Air Flame Retardant Back Fire Air Filter 154222FR fits 2021-2023 Gas Gas EX250 F, EX350 F, MC250 F, MC450 F / 2021-2022 Gas Gas EX450 F / 2019-2022 Husqvarna FC250, FC350, FC450, FE350, FX350, FX450 / 2019 Husqvarna FE250, FE450

This is where it all began. Over 40 years ago, the sandy, gritty soil of The Netherlands - and the resulting engine failures - proved that single-foam and paper filters gave riders air flow, but failed at protection. Twin Air's breakthrough, fused-dual-layer design (now widely copied) combined performance and protection. The fused layers of open-pore foam and fine inner foam trap even the smallest particles. The new, rounder design boosts airflow. So do the minimized seams made possible by a revolutionary micro-gluing process: Shorter seams = more foam = more flow.Replacement filter for use with Power Flow Kit.The Twin Air dual-stage off-road air filter traps even the smallest particles without restricting air flow to offer the best power output without harming the engine.With fused layers of patented open-pore foam and fine inner foam the Twin Air dual-stage off-road air filter protects from dust, dirt, and sand.The special adhesives used in the construction of the Twin Air dual-stage off-road air filter will withstand repeated cleaning even with harsh solvents.Large, flat sealing surface is greaseless.Backfire filters include a laminated layer of backfire-retardant foam.