A few of the covers for these are missing in my house and I can't figure out what to search for for replacements. I'm referring to the dirty, vertical rectangular thing in this picture:
Those are safety catches that prevent the window from being opened all the way.
They pop out, and with the window unlocked, they let it open just a few inches. Supposedly an intruder cannot open the window enough to crawl in, and more importantly a child cannot crawl or fall out.
If these little catches are not in place then all you have are cosmetic closure caps.
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More importantly, they make it (more) difficult for a child to open the window far enough to fall out. Liability management... – keshlam Dec 31 '15 at 5:02
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