Spring strength 3390.

A quick learner from Wilmington, DE says:
April 4, 2017
I am looking to match up a channel balance. The numbers on the unit I have are 3390 EF B.S.I. 33. the Channel measures 9/16" side by 34 long. It matches with Series 351 but I can not find a spring rated for 3390. Can you please advise on how to match this up.
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Casey from SWISCO responded:
April 6, 2017
Hello,
The "33" at the end of the stamp number might be referring to the weight. Remove the window sash and place it on a scale to check first. If it is close to 33 pounds go with stamp 3360, this will carry a weight range of 32 to and including 35 lbs.
If the weight differs just let us know, we would be happy to make another stamp recommendation or possibly custom order a non-standard weight if needed.
34" Series 351 Channel Balance
34" Series 351 Channel Balance
S351-34
$11.73
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