Balance Help

A handy person from Wilmington says:
June 22, 2017
Attached are pictures of the current balancers. The sashes do weigh 50 lbs and the customer does not want them to sag, so it is important we get the right weight of spring in them. Just to remind you this is an excerpt from my original email to you: "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"

We would be looking for a price on 40 units. Is there any more information needed to make sure these fit right the first time. Is it better to order just one and see if it fits or can you guarantee that the ones we order will fit? Do you have anyone in the area that can go onsite and double check, or we can send you one of the broken ones to compare to? Please advise.
User submitted photos of a window balance.
Profile picture of Tom
Tom from SWISCO responded:
June 27, 2017
50 pounds is very, very heavy. We can make it, though it's odd that your old stamp is marked with a "33." However if you're positive it's 50 pounds instead, we can get started on a custom order. Can you just confirm if these are for a lower sash?

These are non-refundable, so you may want to order a smaller quantity to be sure. These have a minimum purchase quantity of 2.
34" Series 390 Channel Balance
34" Series 390 Channel Balance
S390-34
$11.73
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