Insert

An insert of the character described for installation in a hole therefor in parent material comprising a round section body member of which at least part of the exterior of said body member has an increase in diameter between larger and smaller diameter ends thereof, said body member being such as to end locate by its larger diameter end in a hole therefor in parent material;

• and a tubular ferrule adapted to be axially driven about the exterior of the body member when the latter is end located by its larger diameter end in a said hole therefor, the exterior of the ferrule being annularly grooved to provide at least two forwardly and outwardly inclined taper portions in axial succession from said grooves and having a thin section connection at said grooves between them and between the subsequent taper portion and a rear remaining part of the ferrule whereby on the ferrule being axially driven about the exterior of the body member and co-acting with the latter at the exterior increase in diameter thereof, the thin section connection between the taper portions breaks to permit their generally telescopic action so that the subsequent taper portion is expanded by the preceding taper portion so as to have a taper engagement with the wall of a said hole in order to lock the ferrule and body member in the hole with a taper locking action against axial pull out of the insert from the hole.