These Billet clamps are designed to bite and lock into the OEM plastic plenum at the seams to prevent the known issue of the stock plenum failing. The stock plenum, under even stock boost levels, is known to crack and split down the middle. These precision machined clamps pinch and hold the plenum at the seam, preventing it from flexing, causing cracks and/or complete failure. These are a great preventative modification that can save a weekends fun from being ruined! If you're running over stock boost levels we highly recommend these.