| 摘要 |
An electrical outlet box formed of nonmetallic material which has a pair of integral bosses that angularly align, engage and retain wiring device mounting screws therein. The bosses each have a through bore for receiving the screws comprising in sequence a frustoconical surface, a first cylindrical surface having a diameter slightly larger than the crest diameter of the mounting screw threads, and a second cylindrical surface having a diameter slightly smaller than the crest diameter of the screw threads and slightly larger than the root diameter of the screw threads. The frustoconical and two cylindrical surfaces are coaxial, with the frustoconical and first cylindrical surfaces angularly aligning the screw substantially coaxially of the bore and engaging the screw to resist inadvertent removal of the screw from the bore, and the second cylindrical surface threadedly retaining the screw therein upon rotation of the screw along that surface. An annular shoulder is defined at the interface of the first and second cylindrical surfaces.
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