The polyurethane hump coupler is designed to connect to a 4-1/2" OD tube and is 3 long. The polyurethane construction is designed to meet modern elevated engine compartment temperatures with a reaction injection molded (RIM) polyurethane configuration. Standard stainless steel worm-gear #096 clamps provides tight connections, durability and is corrosion resistance for industrial, commercial, truck, off-road and racing applications.