Abstract: A hard metal wear insert to be force fitted into a steel body of a tool or stabilizer which has a serrated cylindrical side surface, as in the prior art, but is provided with air relief passages on the sides to relieve air in the receiving recess as the insert is driven in. A diametrical cross-passage between the air relief passages aids in the expulsion of air and provides a fracture line for destructive removal of the inserts. A central axial passage in conical form allows ready inspection of progressive wear as well as functioning to vent the interior end to prevent excessive air pressure in the heating of the body. A receiving recess in the body is shaped to provide a bottom surface to seat the insert solidly while permitting the air relief passages to function.