Tip: # 1 Tamperproof PhillipsOverall Length: 1"Shank: 1/4" HexTamperproof Style Tip Has Hole In Center To Accommodate Post In Head Of Tamper-Resistant Security ScrewsFor Use With Hand Drivers And/Or Power ToolsDesigned To Withstand The High Torque Of Impact DriversCan Be Used To Install Or Remove ScrewsFully Hardened And Tempered For Long Life Under Constant Use