K&N Individual Round Style Stacks for Hilborn 4, Injectors Fitted to Honda and Kawasaki Engines in T.Q. Midgets - Air filters designed to fit over stock, uncut ram tubes. Filters come complete with rubber mounting adapters. To install, fit rubber adapters around ram tube bases and fit filters over ram tubes and clamp onto adapters in desired position. Air filters come with chrome end caps. Fits #45-K-4A and #45-H-4B Hilborn injectors and are packaged in sets of four. Filters measure 3 inch O.D. x 6 inch L and fit 1 1/2 inch Ram Tubes.