Manufactured by high-temperature sleeve manufacturers, the synthetic material of high-temperature flame-retardant insulating sleeves determines that these sleeves possess many distinctive features that are hard to be replaced by similar materials: high-temperature resistance, thermal insulation, flame-retardant properties, electrical insulation, chemical stability, resistance to climatic aging, cold resistance, water resistance, oil resistance, ozone resistance, and voltage, arc, and corona resistance, especially environmental protection properties, making them substitute products for harmful materials like asbestos.