1.Made from HSS carbon steel, tempered twice, and sturdy. 2.Broken Wire Extractor AD 3MM-10MM With High Hardness Machine Repair Broken Head Screw Extractor 3.Drill bits' diameters and recommended extract diameters of broken screws are etched on each tool. 4.Designed to remove , rusted or stripped screws, studs, bolts, fastener, metal water tap and water tube, etc. 5.used to bore holes on wood, metal, plastic, brick and wall, etc. Drill: High Speed Steel Screw Out Size: 3-10mm Drill Bits Size: 1#,M3-M3.5,2#-.5,3#M5-M7,4#M8-M9,5#M10-M12 Colour: Green Material: steel Package Contents: 20 x Drill Bits 20 x Extractors 4 x Holder Frame 4 x box Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.