| 摘要 |
System comprising a crew and a tool ( 6 ) therefore, in which the screw head ( 1 ) with a slot ( 2 ), the slot ( 2 ) having a first recess ( 3 ) with an approximately straight-walled cross section, and the tool being provided with an engagement section ( 16 ) that is complementary to the first recess ( 3 ). The slot has a second recess ( 11 ) at the bottom of the first recess ( 3 ), with a smaller diameter than that of the recess ( 3 ), and the tool ( 6 ) is provided with a central point ( 17 ) that complements the second recess ( 11 ). The second recess ( 11 ) has a circular cross section and the central point ( 17 ) has a circular cross section. |
