| 摘要 |
The present invention pertains to a concrete screw comprising a threaded portion with threads spirally disposed thereon and a helical conveying portion. In particular, the outer diameter of the threads is greater than the diameter of the helical conveying portion, in which two angled surfaces formed on the end thereof; two flutes are respectively defined between the angled surfaces, a cutting edge is formed on the intersection of one side of each of angled surfaces and two flutes. While screwing, the screw can directly and facilely be firmly screwed into the wall, thus greatly saving the screwing time and increasing the screw efficiency.
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