Blox Racing Shorty Performance 5" Air Filter w/3.5" Velocity Stack and Coupler Kit - Black - BXIM-00323-BKBlox Racing Shorty Performance 5" Air Filter w 3. 5" Velocity Stack and Coupler Kit Black The BLOX Racing performance air filter kit features its "Shorty" 5" height performance air filter, a composite velocity stack, and silicone hose coupler with clamps. Kits are dyno proven to increase horsepower and torque. The dry element filter prevents any sensors from becoming soaked with oil that is normally associated with wet filter brands. BLOX Racing