ALPCA convention souvenir license plates
Since the 1970s, each Automobile License Plate Collectors' Association convention has been accompanied by the issuance of a souvenir plate to commemorate the occasion. The earliest souvenirs were little more than thin-gauge booster plates; but since the late 1980s the plates have been serialed, and often (though not always) carry the same dies and designs used on actual motor vehicle license plates of a respective state.