I have a fairly broken 29" SERIES 795 CHANNEL BALANCE (I'm guessing). I have never done any window repair so I'm sending pics, just in case. I can't find any manufacturer on my windows. I think they are Andersen series 200double-hungs.
There is a small clip at the top which I have included in the pics. I had to dig it out from under a foam-like covering. The inverted link fits behind a notch in the shoe.
There are several plastic pieces that are cracked so this thing is FUBAR.
The ID on the channel is 29D B.S.I. 10