Durable steel material - screw extractor forged from high quality chrome vanadium steel, plus heat treated, rust resistant and sturdy, designed with wide and deep threads for long life Ideal screw removal tool - the tool extractor can be used in combination with a power drill, making it the ideal screw removal tool for home and professional electricians Easy to use - easy to use, first drill a hole in the center of the broken screw, then remove the screw using a suitable extractor Precision machined With precision tapered thread to quickly and easily remove broken or damaged screws and bolts Convenient box delivered in a robust box with screw closure for a quick access and secure storage8 sizes. Application range 4 - 6mm, 6 - 8mm, 8 - 11mm, 11 - 14mm, 14 - 18mm, 18 - 25mm, 25 - 35mm, 35 - 45mm