Abstract: A security slug punch tool is disclosed. A typical application includes protecting curb box cover assemblies employed on catch basins along thoroughfares. The hand held tool houses a first cylinder extending beyond one end of the tool affixed to a smaller diameter cylinder drive pin. A deformable slug is secured within an elastomeric grommet at one end of the tool. An operator forcibly striking the first cylinder causes the slug to be wedged into a face opening in a bolt head, as, for example, a hexagonal opening in a bolt securing a curb box cover assembly, thereby rendering the bolt tamper proof. The punch tool and slug can be configured for securing a variety of bolts with different face openings.