For exhaust gas technique , engine construction , engine warming , aircraft construction and millitary construction
is made of two layers silicone coated glass fiber fabric. It is a kind of High temperature duct, flame retardant, chemical resistance, stand for very high temperature. It is also used in different industry.
Wall : 2 layer silicone fabric, spired tape.
Spiral : spring steel wire hidden between the 2 layers. high-temperature glass fiber cord on the outer surface.