Twin Air dual-stage filters are the choice of top factory teams and riders worldwideDual-bonded foam design filters out even the smallest dirt particles, while allowing more airflow than two separate layer filters (flow bench proven)Flat foam sealing ring provides a secure seat against the airbox, even in the worst riding conditionsTwin Air filters are slightly smaller than stock, making them easier to change while increasing dead air space around the filter for better performanceBackfire filters include a laminated layer of backfire-retardant foamAir filter cages available separately for some models