AllAiraid Premium Filters use a synthetic filtration media called SynthaFlow.SynthaFlowis a synthetic nano-fiber material that traps the smallest dirt particles that ordinary cotton-gauze "performance" filters can't capture. Based on SAE standards, Airaid Premium Filters with SynthaFlowtechnology, capture almost twice the percentage of 2 micron particulates and more than six times the amount of 0.5 micron particulates than our competitor's filters. Airaid Premium Filters are constructed using the finest materials available today. All Airaid Premium Filters utilize a hand-poured urethane body that won't crack, curl or shrink like other rubber or plastisol units by our competitors. All Airaid Premium Filters are 100% washable and reusable.