Tap knob inserts

There were 2 cigar boxes that held these tap knob inserts.They were saved by a gentleman that worked at the Green Duck Co.(which made emblems,badges and advertising items) in Chicago during the 30's and 40's.They also survived two separate trips to the trash bin over the decades.It was costly to do so,but I had the outer knobs remade that held these inserts (with a 2008 trademark) so they could be complete.Hot rodders sometimes used these tap knobs for gear shifters.These are called "ball knobs" and the older ones were made of bakelite or catalin with an enameled insert.