| 摘要 |
A recessed head screw includes a head portion having a driver-engaging part between top and bottom faces thereof. The driver-engaging part includes a recess extending downwardly from the top face, four spaced-apart slanting walls slanting downwardly and convergingly from the top face, and four first bearing pieces each spacing two adjacent ones of the slanting walls and each having a four-sided first bearing face, and two substantially triangular second faces interconnected by the first bearing face. At least two second bearing pieces extend downwardly and respectively from bottoms of two opposite first bearing pieces. Each second bearing piece has a connecting face, and a third bearing face extending downwardly and inwardly from the connecting face. The connecting face inclines with respect to both of the third bearing face and the respective first bearing face.
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