Specifications:4pc screw & bolt extractor drill bits & guide set, broken easy out fastener kit.Removes any screw or bolt! (Flat, Hex, Painted & More) Durable hardened steel construction. Quick & easy to use. Works w/ any drill. Removes any stripped screw in 10 seconds or less. Even works on jagged, uneven, or rough breaks. Self centering tip, no walking.Compatible w/ quick connect chuck systems. Usage:1. With the speed can be change and -direction of the electric drill.2. The first thing to determine when using extractor and ensure the safety of the tool and will not be moving.3. The screw head be damaged thicker than extractor, with the drilling head end drill a hole( deep enough) in the middle of the screw head.4. Reverse screw extractor and into the damaged screw counterclockwise, until removed.Type: Screw Extractor Drill Bits Guide SetColor: As the Pictures ShowMaterial: Alloy SteelQuantity: 4 PcsFeatures: 4 in 1, Useful and Practical Tool, Portable1# Extracted Diameter: 3mm - 5mm/0.12" - 0.2" (Approx.)2# Extracted Diameter: 4mm - 8mm/0.16" - 0.31" (Approx.)3# Extracted Diameter: 5mm - 10mm/0.2" - 0.39" (Approx.)4# Extracted Diameter: 6mm - 12mm/2.36" - 0.47" (Approx.)Total Length: 51mm/2.01" (Approx.)Notes:Due to the light and screen setting difference, the item's color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.