Thermo-Tec 17063 Black 5/8" X 36" Thermo-Flex Wire-Hose Insulation The combination of aluminum, silica and stainless steel is combined to produce a sleeving that is flexible, lightweight and strong The aluminum-silica combination can be slit for applications such as wire looms or hose covering without disconnecting the ends of the wire or hoses Thermo-Flex Aluminum can withstand extreme temperatures of up to 750 degrees Fahrenheit