Double Wall Silicone Hose is a popular choice for brake cooling ducts due to its high-temperature capability and extreme flexibility.  Temperate ratings for the hose is 450 degrees continuously and 500 degrees intermittently. The hose features extreme flexibility with a spring-steel wire which supports the hose from collapsing.

The hose ships as 12′ long sticks.  These sticks are 12′ when tightly stretched and may be slightly smaller when relaxed.