Hex Head Allen Wrench Bit Set Screwdriver Electric Power Drill Metric Quick Release Adapter Screw Driver Security Magnetic TipsHex Head Allen Wrench Bit Set Screwdriver Electric Power Drill SAE Metric Quick Release Adapter Driver Security Magnetic Tips Precision and Durability: hex head drill bit set are made of high quality S2 alloy steel, processed using CNC precision technology, and undergo a special heat treatment process that gives them a hardness of 58 60HRC. This ensures long lasting durability and precision, even under heavy use. Easy Identification and Use: Allen