Green Air Filters are washable and reusable air filters that not only look great, but trap more dirt, fit better, and have greater airflow than the competition. Their new technology uses two layers of woven cotton. The first layer boasts a medium knit that traps bigger chunks of engine-choking filth. The second features a super-fine weave that captures particles down to 5 microns, which translates to more power, longer engine life, and better fuel economy. Green Air Filters run up to 50,000 miles between cleanings.