HIGH PERFORMANCE Filter Kit for MAC Air Helmet Pumper, designed for extreme dust, dirt, and silt particulates, incorporates a 3-stage filtration system which includes a micron paper filter, washable foam intermediate filter, and pre-filter. The kit provides 6.5 feet of filtering media, 18% more than conventional filters. Greater surface area is achieved through deeper pleats, trapping more particulates. Larger particles are thwarted with a heavy-grade interior wire mesh, while an open cell foam filter adds another layer of protection. An outer micron pre-filter works to prevent most particulates from interfering with airflow while extending the lifespan of your paper filter. When dirty, the paper filter is replaceable, while the other filters are washable. Each kit includes a high-performance micron paper filter, a washable foam intermediate filter, and a washable pre-filter.