“Because you lead by example, your companions gain benefits from your methods of exploration. If you're concentrating on keeping a follower with you for the foreseeable future, it's well worth augmenting them as much as possible, though this always comes at the expense of spending points purely on yourself. But that's selfish.”— Fallout 4 Vault Dweller's Survival Guide description
Once obtained, it can be discarded to take a single companion from another player character or from the shop. It will also unexhaust all companions in the player character's inventory, ignoring their requirements.
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