Trouble With Atrium Sash Ballances

A quick learner from Arizona says:
There were two windows that the balancers fell out of that were different widths. As such, there were two different part numbers listed. I assume one has a heavier spring even though they look the same. The windows have a "Atrium" logo on the top. The pictures are attached of the two balances.

Below is the information you may need in order to tell me what item I need t purchase from you. The part number listed is printed on the balances that came out of the windows


- part number 34-4 KX CMC 11, the metal portion is 1/2" x 35". Total length from tip of plastic to tip of plastic is 36" (need 2 -one each side of window. The sash slides upward and it weighs 15.7 lbs.

- part number 34-5 BA CMC 11, the metal portion is 1/2" x 35". Total length from tip of plastic to tip of plastic is 36" (need 2 -one each side of window) The sash slides upward and it weighs 25 lbs.
User submitted photo of their window hardware.
Profile picture of Tom
Tom from SWISCO responded:
These look like our S395-35 channel balance. One would require a 3440 option and the other would need a 3450 option. Look this hardware over and see if you agree.
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