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This is an old nylon double-leg corner that hasn't been made in a long time. The good news is that you can use our 95-002 corner key as a replacement. What you do is use the 95-002 to hold the frame together while you install it into the channel that is closest to the screen groove. You'll then need to use one leg of your existing nylon corner (or, alternatively, one leg of the 95-002) to hold inside the slide latches on the bottom channel of the screen frame. It's a little awkward, but it does work.