Terminated: unknown
This is one of a series of CASIO "Mini" calculators, the first one of which was introduced as a low price calculator in 1972.
The display has a peculiarity, the zero is lower case! I don’t know any
other calculator series apart from the early CASIO’s that have a lower case zero.
Shown here is how the number "4010" is displayed on this calculator.
The calculator runs on batteries as well as on a power adapter.
Operations are repeated when repeatedly pressing the = key.
CASIO has created a calculator watch to pay hommage to this and the other CASIO minis, now sold out. The CASIO CA-53WB-1B, CA-53WB-3B and CA-53WB-8B. See this CASIO page (link validated 2026-10-06). Whilst I like that CASIO has created this hommage, I personally do not think its a particularly good one. The CA-53WB-3B representing the calculator on display here doesn’t even have white number keys.