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        Summary 
        
         
          
           | Description | 
           
             English: A photograph showing two lag screws, also called lag bolts. The pen and the toothbrush are shown for scale. These particular lag screws are a half-inch-by-6-inch and a 3/8-inch-by-4-inch, both with  hex heads (that is, external hex) and made from  steel with a bright zinc coating (electroplated  galvanization) for corrosion resistance. Dull gray coating with  hot-dip galvanization is another common coating. The heads are cold-formed in a die, and the threads are rolled in another die. There is no machining (metalcutting) needed. See also  File:Lag screws aka lag bolts 001.png. 
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           | Date | 
           26 August 2011 | 
          
          
           | Source | 
           Own work | 
          
          
           | Author | 
            Three-quarter-ten | 
          
         
         
        Licensing 
        
         
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           I, the copyright holder of this work, hereby publish it under the following license:
           
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       File usage
       
        The following pages on Schools Wikipedia link to this image (list may be incomplete):
        
        
       
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