System1 Designs 3.5" Inch Black Straight Silicone Coupler 3 Layers of Polyester Reinforcement Suitable High Quality Intake Intercooler Turbo Pipe Intercooler with 2x T-Bolt Clamps System1 Designs line of silicone couplers feature 3 layers of polyester reinforcement and are suitable for applications with boost pressures up to 45psi. They also feature a temperature rating of 428°F for direct to turbocharger installations.