aFe Magnum FORCE CAI Univ. Silicone Coupling Kit (4in to 3.8in ID / 2in L) Reducer Coupler - Black

The high temperature injection molded silicone reducer coupler is designed to connect to a (4" x 3-3/4") OD tube and is 2" long. Standard stainless steel worm-gear #060 & #064 clamps provides tight connections, durability and is corrosion resistant for industrial, commercial, truck, off-road and racing applications.