 They were developed as an alternative to pitons, which are hammered into cracks, damaging the rock.Most commonly, a carabiner will be used to join the hex to the climbing rope by means of a loop of webbing, cord or a cable which is part of the hex.Hexes are a type of nut, a hollow eccentric hexagonal prism with tapered ends, usually threaded with webbing, a swaged cable, or a cord.