Need some help

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For some reason, I think the one in this pic is backwards. This piece acts like a drywall anchor. The "barbs" will spread out when the bolt goes all the way in. That will retain it on the outside of the glass. I could be wrong. Please post a pic of yours when you get it installed. I'll be doing this in about a month. Thanks
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That is the plastic rivet you're showing, what he has in his hand is the window travel down stop.