Abstract: An insert for installation in a hole therefor in parent member comprises a body having an exterior increase in diameter between larger and smaller diameter ends and a ferrule adapted to be axially driven about the exterior of the body when the latter is end located by its larger diameter end in a hole therefor in parent material whereby the ferrule is expanded as a result of co-action with the body. The ferrule is annularly grooved to provide one or more forwardly directed portions therefrom shown of forwardly and outwardly inclined taper form at or adjacent the leading end of the ferrule and having a thin section connection therewith at the annular groove or grooves so that on axial co-action of the ferrule with the body the forwardly directed portion or portions effect radial expansion of the ferrule into taper engagement with the wall of the hole in order to lock the ferrule and body in the hole with a taper locking action against axial pull out.