Channel Balance 29-6 stamp

A quick learner from florida says:
Hi please help me to replace these block and tackle window springs.
I have attached pics also.

30" channel
the window sash weighs 31 pounds.
stamp on channel is - 29-6 IA2 cmc6

Thank You
A customer submitted photo of a window balance.
A customer submitted photo of a window balance stamp.
A quick learner from fla says:
I have attached more pics of my guides.
User submitted photos of channel balance attachments.
Profile picture of Paul
Paul from SWISCO responded:
You're going to need Series 385, but I will need the weight of your sash to see for sure. Please remove your sash from the frame and place it on a scale to get an accurate weight.
A quick learner from fl says:
Hi Paul, I already told some one there the sash was 31 lbs.
A quick learner from fla says:
Hi Paul my sash is 31 LBS so do i go wit the 385 series 2950 option?
Profile picture of Tom
Tom from SWISCO responded:
Yes, the option 2950 should do it for you.
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