Hybrid Racing Cold Air Intake System (06-11 Civic Si)Full Silicone Construction Most powerful 8th Gen intake on the market Built In Air Bypass helps to prevent hydro locking Includes 3. 5" velocity stack & filter Includes battery relocation kit Comes with couplers for large and small throttle bodies Requires tuning software like FlashPro Description Vehicle Fitment Install Guide Big tube, big power! We spent countless hours designing, testing, and refining this design to ensure it was the absolute best