An enclosure includes a base unit and a cover unit that snaps into the base unit easily, but is difficult to remove from the base unit without knowledge of the appropriate disassembly technique. The appropriate disassembly technique includes the application of pressure at key regions of the base assembly. The application of pressure at the key regions distorts the base assembly so as to disengage key portions of the cover unit from the base unit. The cover unit includes protrusions having an inclined surface and a flat surface. The inclined surface facilitates manufacturing assembly, and the flat surface encumbers the disassembly of the enclosure. The application of pressure at the key regions distorts the base unit so that the flat surfaces of the protrusions on the cover unit are disengaged from the base unit. In a preferred embodiment, the base unit is a resilient insulating material, such as plastic, and the cover unit is a shielding and heat sinking material, such as sheet metal.