Window balancers

A quick learner from Naples Fl. says:
1/2 inch wide, 30 1/4 long. The only markings are the numbers 2940 and the letters NM or NN BSI.
Thumbnail of the uploaded file named FE175A10-C85C-4213-B562-BA3A88AD500B.jpeg
Profile picture of Casey
Casey from SWISCO responded:
Hello,
We'd be happy to recommend a replacement balance but we will need to see the attachment on the opposite end of the metal channel as well to compare to our replacement options. Also, make sure that you are measuring just the metal channel when determining the length since it would normally be 30" exactly. Thank you!
A quick learner from Naples Fl. says:
Hi Casey, the metal is exactly 30 inches long. I am attaching pictures of the ends which are plastic.
Thumbnail of the uploaded file named 9D86AD6F-FC25-4A8E-9549-E73FA70C6D40.jpeg
Profile picture of Casey
Casey from SWISCO responded:

Perfect. I believe I see tabs that we commonly refer to as wings on your bottom attachment. If so, take a look at our S377-30 channel balance with a 2940 spring strength option. Please let us know if you have any other questions.

A quick learner from Naples Fl. says:
Looks good. I will way the window to make sure that 2940 is right. Thanks
Profile picture of Casey
Casey from SWISCO responded:

It never hurts to be thorough. Please let us know if you need anything else. 

Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)