I favor simplicity in all things, and while sometimes combining devices results in greater complexity, in this case it seems to simplify things. It’s possible, however, that the reason nobody has made one of these before is that something about it doesn’t work.
Even if that’s true, however, this thing also
doublestriples as a weapon. That’s three devices in one!
It only costs $7 and you can get it cut by any key-cutting-type person. If you’re really intrigued, you can buy a 30% interest in the Split Ring Key if you’re the investing type.