This print is designed to press fit onto a 12V car battery terminal to cover the exposed metal parts of the post to prevent accidental short circuits.
This model allows for protection of N70T type posts which are often found on Deep Cycle Batteries and have two posts for each terminal (see photo).
My “negative" terminal cover is found at: https://www.prusaprinters.org/prints/110704-12v-car-battery-cover-negative-terminal
The author hasn't provided the model origin yet.