Fatz Fabrication 7" Air Filters7 Long element, 4 Outlet filters. Our Fatz build 7 inch air filters are quality made filters, built specifically with Off road driving in mind. We have options for Dry elements which have a filtration efficiency of 99. 9% or 8 Layer gauze elements which have a filtration efficiency of 99. 5%. We have been using our specific material specifications for many years and have carried out real world testing in vehicles from daily driven vehicles to off road