Accel Kool Blue air filters are designed to not only be the best filter you'll ever buy, but also the last. They're constructed from 100 percent surgical cotton gauze that's sandwiched between layers of blue epoxy-coated, galvanized steel wire mesh. The fabric is soaked in oil and stops dirt particles as small as 2.8 microns from entering your engine. Plus, this design enables the air to flow faster through the filter, increasing horsepower and torque. These filters are completely washable and will last the life of the car with proper maintenance.