This is a pack of four Lucky 7 RC 1/8 Off Road Air Filters, and are intended for use with the Pro-Line air filter system. Lucky 7 air filters are precision cut two stage filters that offer excellent air filtration and protection for your engine in the harshest conditions. A unique ribbed pre-filter provides almost twice the surface breathing area when compared to a standard flat pre-filter. When you combine these filters with Lucky 7 filter oil, you have a system that not only provides unmatched engine protection, but also an optimum foam density to oil viscosity ratio for incredible air flow. Conveniently packaged in a 4mil zipper bag, these filters are easily prepped and safely stored so they are ready to use when you need them. Dont roll the dice with your equipment, get Lucky.