The window is a double hung that tilts out for cleaning. Window is from unknown manufacturer and could date to the 1960's. This picture is from an identical window and shows what the part should look like. Whatever the part is called it holds the window in the sash.

We took the window out of the sash to get a good view of the part so the angle of the picture is all wrong. In this image the edge you see is the left side of the window and the part I'm trying to ID is at both bottom corners

I had a window company look at the window and they were clueless. Hoping I can find a replacement part online.

Attached Images

IMG_3043.JPG (67.4 KB, 127 views)

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Dennis
SWCA #2409, SWHF #353

Might be called a sash guide. You'll have to do a little looking but can probably find them on the net.
Do you know the manufacturer?

Might also be called a sash retainer.

You might check this site.

Products Archive - Window Repair Parts