| 摘要 |
A deck screw for use with plastic and plastic composite deck materials has a shank with a lower segment having a right hand thread and an upper segment having a left hand thread. The upper left hand threaded section has a major diameter which is the same as or slightly less than the major diameter of the lower right hand threaded section. The deck screw evacuates and eject loose material cut out from the deck material as the screw penetrates the deck material, preventing undesirable unsightly deformation of the deck upper surface. |
