Fitting type : Locknut IndoorOutdoor : Indoor Item Package Type : Bagscarton Material : Galvanized Steel Trade Sizes: from 12" to 4" Field Names: Lock nuts, conduit nuts, locking nuts, jam nuts, coupling nuts, pipe locking nuts, locknuts. Application: These heavy-duty locknuts are used in dry locations to secure threaded conduits or connectors to electrical junction boxes or enclosures.