Nut (climbing)

In rock climbing, a nut (or chock or chockstone) is a metal wedge threaded on a wire, used for protection by wedging it into a crack in the rock. Nuts come in a variety of sizes and styles, and several different brands are made by competing manufacturers. Most nuts are made out of aluminum. Larger nuts may be threaded on Dyneema cord instead of wire, but this has become unusual. Nuts are related to, but not interchangeable with, Hexcentrics.
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