These plates are issued to taxis.
This type started in 1931, with a “TAXI” legend. This type continued in an all-numeric format on various bases until the mid 1980s. Around the time of the introduction of the map base in 1987, a T1234T was used.
Click the image to see this type in use.
Beginning with the 1967 expirations, the colors were reversed to blue on white. This scheme lasted until the general reissue in 2000.