Designed for Screw; Bolt Extracting: Each bit has dual head designs, one is used to drill a hole in the middle of the the damaged screws or bolt with the drill end, the other is used to extracting it. The special design helps you grab and remove the screws precisely and easily in 10 seconds or less. Multi Purpose: 6 different sizes of bits ( 0, 1, 2, 2, 3, 4) are included in package of stripped screw remover kit and 0 is a gift provided for extra using. All is for ensuring that the screw extractor kit can meet all of your needs. Great for removing stripped, broken head, rusted, unscrew, free-spinning and deck screws or bolts. H.S.S 4341 Material: Stripped screw extractor is made of high quality H.S.S 4341 material, has 63-65 HRC hardness which is harder than most of other similar products. Durable and solid, suitable to removes even the most stubborn stripped, damaged, embedded, rusted and painted-over screws and bolts. Best gift for any craftsman. Easy to Use: 3 simple steps: 1. Drill out, 2. Flip Bit, 3. Extract. Just no other tools needed but a drill, select a smaller bit than the damage screw, you can easily remove the screw. Note: please make sure to run the drill in reverse during the process. Wide Application: The screw and bolt extractor can work on Allen bolts, Machine Screws, Lag Bolts, Wood Screws, Hex Bolts, Sheet Metal Screws, Rounded Bolts to name a few. Meanwhile, comes with a box which make it so portable for easy carrying.