Mishimoto has developed silicone hoses for your STI.Mishimoto Subaru STI USDM Silicone Intercooler Hoses are made from a combination of high - grade silicone and heat - resistant embedded fibers to handle high temperatures and additional boost pressure.Each hose has a smooth interior surface to deliver increased airflow to your Subaru STI intercooler.Available in black, blue or red, Mishimoto silicone hoses retain OEM fitment while providing increased pressure tolerance for the ultimate upgrade in performance and style.