This is the latch for double hung windows that keeps the lower window from folding inwards. I'm not sure of the Window manufacturer, but they were in my apartment and I broke a few of them installing air conditioners. I took one that wasn't broken and measured it to create this. You need to print both the body and the latch as I can't guarantee either of these parts will fit the corresponding OEM part. You will also need the OEM spring from the broken parts.

Assembly can be a bit tough, I suggest warming the main part, specifically the two prongs that hold the slide in place, otherwise they might break. I lost the original part files, so I can't modify the prongs to make assembly easier and I no longer have access to the windows to re-create the original design.