I have a 1 sided Möbius strip die that I call Predestined Choice. If a player wants to do something that goes against fate, or a deity that controlls time/events etc. I tell them to roll for predestined choice and hand them the die. More of a joke than a feature, but it could be the same for an all 5 sider
Clacksmith
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My bet is it's one of a set of cheater's dice, with the other one having only 2's and 6's, leading to all rolls being 7 or 11.
In my collection, I've got an "all fives" die, and a matching (2,2,2,2,6,6) die. Presumably this is what it is for.
Best lead that I could find for you is Sicherman dice, albeit without all same numbers and instead a wholly different arrangement: https://en.wikipedia.org/wiki/Sicherman_dice There might be some trend to the production of non-linear numeration of six-sided dice, but I'll be damned if I can think of what it is so best of luck.
I'd guess for a display where the die could move around, but you want it to always show 5.