Tekagi

Tekagi were three back-curved barbs that protruded from a metal band wrapping around a shinobi's palm (or, less commonly, the sole of the foot). They were primarily a climbing tool, making climbs easier and allowing shinobi to attempt to scale surfaces they otherwise could not. But they could also be used to swing at and bludgeon a foe when they hung loose from the wrist, or to slash them when attached to the palm. Defensively, a pair of tekagi allowed a shinobi to snap a metal blade by catching it and applying lateral pressure to the flat of the blade. Because shinobi were used to wearing tekagi, they sometimes punched with a strangely shaped fist, forming a blade with the fist's protruding knuckles and bracing the fingertips against the tekagi band.