The part stamp reads 3020. I have no idea what company. The non-tilt windows with this spring balance have it on only one side of the window. The channel balance broke through the top cap. Additional parts needed are the take out clip and sash guide. I presume the channel balance comes with the top and bottom plastic pieces.
This is the second time I am replacing this part. The spring in my previous purchase was too strong.
Thanks for your assistance, Judy