Lawson 313, pretty uncommon to begin with, with 24-hour display.

I’ve heard several explanations for the purpose of these 24-hour clocks. One is that they were used by radio stations to mark station breaks. Another is that TV viewers liked to keep track of the time so as not to miss their favorite show. I like this second explanation better because these uncommon versions (which do not seem to have unique model numbers) have a hidden feature – they light up!

No switch so it’s always on unless you remove the bulb.

If you know more about the reasoning behind these 24-hour clocks, please let me know.