Andersen window sash balancer

A quick learner from Maryland says:
July 11, 2020
I need help identifying the correct replacement sash balancer for a double-hung Andersen window installed in 1987. It's a double pane window with CIG-2 3-87 IGCC CBA High Performance printed in the corner of the glass. The panes are approximately 35x29. I attached a few pics. From other posts I read you asking folks for a stamped 3 or 4 digit number. I looked closely and didn't see a number like that. On one side is 11600-17 and stamped U4 11L 9-87. On the other side there is a very faint copyright number and date. I see no numbers on either side of the stapled tab. Thanks for your help.
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Bob from SWISCO responded:
July 14, 2020

For an Andersen balance with the stamp '11L', you can use our 24-11L. Note that for this particular product, the opposite-handed side of the sash will use a different balance: see the 23-11R. 
Andersen Sash Balance, 11R, 10SR
Andersen Sash Balance, 11R, 10SR
24-11R
$54.20
Andersen Sash Balance, 11L, 10SL
Andersen Sash Balance, 11L, 10SL
24-11L
$54.20
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