The extractor is made of 4341 high speed steel. If it is made of stainless steel, the bit end of the extractor can hardly be drilled, and take out screws are easy to slip, so it is not applicable. If the hardness of the screw is high and drilling is difficult, you can use your own fried dough twist drill to drill the hole first, and then use the extractor to reverse and take it out.
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