Composits hollow insulators are composed of FRP tube with silicon rubber housing and metal flange,which is suitable for indoor and outdoor HV equipment.Developed since thirty years ago while gained in service near fifteen years,composite hollow insulators are more adveanced than porcelain insulators,especially in specific requirement and operation environment,it behaves prethy well in respect of service safety and handling.The insulatprs confirm to GB/T21429-2008