Trident 3 1/2" ID hand made Blue Silicone Hump Hose Bellows provide the ultimate flexible connectors for Marine Wet Exhaust Systems. They offer much greater tolerance to heat , misalignment, engine movement, & vibration, with significant savings in cost, parts, labor and space. Highest max. continuous operating temps. Blue Very Hi Temp: Silicone 350°F (177°C).