| 摘要 |
The invention relates to a handtool and screwed fasteners. The invention ensures the long service life of screw drives and wood screws and the processabilty thereof. The screw consist of a head and a working end with a screw thread. The slot in the head for the screw drive is dovetail-shaped. The working end of the screw drive for screwing in and off the screw is made in the form of the mirror reflection of the slot of the screw head and with the same tilt angle.
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