Electrical insulators being electrical insulating tapes made of alumina-fiber materials; electrical insulators being electrical insulating sleeves made of alumina-fiber materials for semiconductor manufacturing machines and power lines; chemical fiber thread and yarn, not for textile use; insulating materials in the nature of inorganic alumina fibers and alumina-silica fibers, all not for textile use; rubber thread and covered rubber yarn, not for textile use; inorganic-fiber threads and yarn...