Marking up all of your tools makes it tough for thieves to resell your stolen property. It also prevents other workers on the jobsite from accidentally mistaking your equipment for theirs. The best way to give plastic tools your mark is with a soldering iron. Just heat it up and then draw/melt whatever you want directly on to the tool itself. Be sure to make your mark on the actual body of the tool and not a part that can be easily removed, as that sort of defeats the purpose.
Check out this story for more great jobsite security tips.
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