The seller packaged this very poorly in a loose envelope so the piece of plastic holding the seal has broken off and there is no way to reattach it . It doesn't matter as it sits between the dock and the laptop and doesn't need to be locked unless you're constantly moving the dock. Strangely enough, you have to buy it separately for the dock, it should simply be included in the kit and then not used up unnecessarily. I had to buy two of these for two different laptops.
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