| 摘要 |
CiNRPonbhIDCCEJIL S$II71j I 0OC.21/0K/20112 A screw fastener having a head with a peripheral surface configured to apply a driving torque to the head by an external driver tool, the head including an axially-directed hole for 5 receiving an axially-directed pin of the driver tool whereby engagement of the pin within the hole acts to maintain the driver tool engagement with the screw head during driving of the screw. |
