Window balance,

Hey there,

Thanks for reaching out to us! The balances you are searching for are an extended travel channel balance and will need to be custom made assemblies. I'm happy to get the quote made up for you for all (16) of these assemblies but I'll need to confirm a few details before we move forward.

The stamp from the balance is what denotes the weight range a balance should be able to hold. Are you certain that all 16 balances have the same stamp? If not, you'll need to take a look at each stamp from the balances you are looking to replace.

You'll also want to confirm the length of the metal channel, not including the top and bottom attachments.

Please let me know if you have any questions in the meantime.

The stamp only denotes the weight range the balance can hold, it cannot tell you the series balance you have. While these are BSI balances, these are not common. 

There are quite a few notable differences between a "standard balance" and an Extended Travel Channel Balance, which is the one you have pictured here.

• The length of the metal on this balance should be 27-5/8". A standard balance is made in whole number increments. The standard balances would not hold up very long in the window given the difference in the travel length.
• The shoe on the balance is much different than the one installed on a standard balance. Extended Travel Balances have a shoe with a wheel installed directly into them. It also has a much different shape and it has a hook attached to the bottom of it.

It would not be advisable to use a balance different from the one originally installed in the window, however you will need to make that decision. Keep in mind, there is a potential risk for causing irreparable damage to the sash or the window frame.

I hope this helps!