This Damaged Bolt Set (#0/#1/#2/#3/#4) Is Suitable For Most Drill Bits And All Screw Sizes Or Bolts, And There Is a Box For Storing These Screw Extractors, Very Easy To Carry. The Screwdriver Is Made Of 4241 High-Quality Speed (Hss4241). The Threaded Head Has a Firmer Grip And Is More Convenient To Use. Suitable For Any Drill, Any Screw Size Or Bolt. And Can Even Remove The Most Stubborn Bolts And Screws That Are Peeled, Damaged, Embedded And Painted. This Is a Very Simple Step. Just Choose a Drill Bit Smaller Than The Damaged Screw, You Can Easily Remove The Damaged Screw. Suitable For Power Tools With Chucks Or Joints, Suitable For Loosening Screws Or Broken Nuts On Hardwood Or Wooden Boards.