摘要 |
A non-slip screw of the type having a threaded shank and a slotted head, including a locking surface defined in the screw head by a central transverse slot which extends across the top of the head for engagement with a screwdriver blade tip. The locking surface includes a pair of radially outwardly extending inclined walls extending downwardly from each end of the transverse slot. An especial screwdriver having its exterior blade tip configured complementally with the pairs of radially outwardly extending inclined walls is engageable with the locking surface, so as to rotate the screw head in either direction. The screw head is characterized by its positive grip with the screwdriver blade tip, notwithstanding actual screwdriving or unscrewing and removal of the screw.
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