polymeric insulator,strain type(suspension type insulator) 1.Fiber Glass rod 2.Silicon rubber shed 3.For strain string Our composite insulator is made of ... rubber has passed 1000 hours test from CESI Italy,and insulator can be tested according to IEC standard for all tests ... , type test, dy penetration test,boiling test and so on.Insulator made by TCI has been exported to many coutries from ...