If something is hanging by a thread, it usually denotes that it is ready to fall apart or that the situation can change in an instant. The phrase can be applied to physical things, situations, and ideas. The term hanging by a thread, derives from the banquet that King Dionysius held for Damocles, a courtier of ancient Syracuse. King Dionysius was beginning to become annoyed with Damocles’ constant flattery of his king. He invited him to a banquet, where Damocles was seated under a sword suspended by a single hair. It was said to symbolize his tenuous position in the court. It was not only the sword that was hanging by a thread but also Damocles’ life. This also gave rise to the idea that someone can have the sword of Damocles hanging over them, meaning they are in a very precarious situation.
The cache you are seeking is a bison tube attached in the obvious location.