Wouldn't have known anything about this before some googling. Here's a summary of said googling, for what it's worth.
I found a whole bunch of tokens on numista.com; beer, bank, "automatic" etc
Some of the bank ones are referred to as "safe deposit" tokens, like the following.
https://en.numista.com/catalogue/pieces160441.html.. though how they were actually used isn't explained. If I was guessing, i'd maybe say they were issued on the day in the bank when someone wished to access their box, and then used to enter/exit the safety deposit box area. The boxes themselves would obviously be controlled by key(s).
Also found this:
https://en.numista.com/catalogue/pieces140974.html.. which nicely matches the cutouts on the OP token but, again, no explanation as to its usage.
It might also be for car parking at a bank.