Bolt (climbing)
In rock climbing, a bolt is a permanent anchor fixed into a hole drilled in the rock as a form of protection. Most bolts are either self-anchoring expansion bolts or fixed in place with liquid resin.
While bolts are commonplace in rock and gym climbing there is no universal vocabulary to describe them. Generally, a bolt hanger is a combination of a fixed bolt and a specialized stainless steel hanger designed to accept a carabiner, whereas in certain regions a bolt runner describes a hangerless bolt (where the climber must provide their own hanger bracket and lock nut).