Identifieding channel balances

A quick learner from Long Beach Ca says:
Can you tell me if these are the 351 series balancer 27" long .The stamp read 26 5 JW CMC 7. On the shorter balanced is read 12 1 BSI TD .I measure it and it 12 1/2 " long .
User submitted photos of a window balance.
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Tom from SWISCO responded:
Thanks for contacting us! No, our Series 351 will not replace this. You have a special balance that has to be custom made. We can help, for sure, but before we go any further can you first confirm that the longer balance and shorter balance are identical in every other way? That is, are the nylon attachments and metal clip exactly the same? If they differ at all, I will need to see some pictures of those features of the shorter balance. Can you also tell me how many of each that you need?
A quick learner from Long Beach says:
Other than both being 5/8 in width ,there is nothing identical between these two balancer .I need 1pr of the small and 3pr of the larger one .
User submitted photos of a window balance.
Profile picture of Tom
Tom from SWISCO responded:
Ah, I see. That's a pretty big difference! I couldn't tell based on your first post since you showed the nylon attachments for the short balance, but the stamp for the longer one. It looks like the shorter balance has to be custom made, while the longer one could either be our Series 390 or Series 351 standard channel balance. I cannot confirm which one as I cannot see what the size of the nylon shoe is (that is the only difference).

For the short one, there is actually a minimum purchase quantity of 2. Would that be acceptable? If so, I'll send you a custom order form and price quote for a pair.
A quick learner from Long Beach says:
Yes that is fine ,I'll order 2 pair if it not to expensive ,otherwise can I just buy the little metal clip that look like a hook .As far as the larger one ,I need 3pair of those and it look like it the 351 .What can I look at to make 100% sure that what it is ,or what would you like me to take a picture of so you can determine it yourself .
Profile picture of Tom
Tom from SWISCO responded:
Great, I've emailed you a custom order form for 4 of the shorter balance. You should receive it shortly. It includes a price quote.

The best way to determine if the S351-27 is a match is to carefully go over our pictures and measurements and use your best judgement.
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