Anyone that has played zombies in Call of Duty: Black Ops 3 long enough has no doubt used a Summoning Key before, as it plays a major role in the story. Its main purpose is to trap the Shadowman so that the crew can remove the curse that is the Mark of the Beast from their hands.
Aside from removing curses, the Summoning Key also just looks pretty cool, too. That is exactly why one Redditor decided to show off the one they made in real life.
In the post, Thebandit1982 showed off a detailed look at the Call Of Duty: Black Ops 3 Summoning Key that they created with their father. While the post was eventually taken down, we were able to grab some screenshots from the eBay page for the item, which you can see below.