Nuts
A wedge- or hexentric-shaped piece of metal, generally made of lightweight aluminum, that is snugly placed in a crack for a lead climber’s protection or as a belay anchor. Nuts, made in various sizes and shapes to accommodate many crack sizes, are an important climbing tool since they do not damage the rock with repeated insertion and removal. The first climbing nuts used were actual nuts for bolts that were picked up along railroad tracks in England and threaded with a thin cord. Some types of nuts are Hexentrics and Stoppers.
