This is an 8" round 'hubcap' style enameled telephone sign. The Bell Co logo dates this sign to 1921-1939. This kind of sign makes a good go-with to your insulator (especially telephone insulators!) collection. Some telephone companies had glass pin types made with their name on them along with enameled signs too. Like: Southern Bell Tel & Tel, New England Tel & Tel, etc. This sign was once in the collection of A.W. Merrill.