Squirrelly 4.0" to 4 inch 90 Degree Elbow Silicone Coupler Hose Intercooler Piping Intake Black Squirrelly's line of silicone couplers feature 3 layers of polyester reinforcement and are suitable for applications with boost pressures up to 45psi. Size: 4" 90-Degree Material: 3-ply Polyester Reinforced Leg Length: 3.5" Temp: 428 Degrees F (220 C)