Sash spring for a Kolbe $ Kolbe window

A contractor from Boston says:
Hi,

I have a Kolbe & Kolbe window that needs new sash springs. It has a number on the back that reads 2650 bsi and its 27" long. Do you have a match for this?

Thanks
Dennis
Thumbnail of the uploaded file named 2650 BSI stamp
Thumbnail of the uploaded file named silver metal knife lock shoe
Thumbnail of the uploaded file named full view balance
Thumbnail of the uploaded file named long silver clip
A contractor from Boston says:
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Thumbnail of the uploaded file named gray metal shoe
Thumbnail of the uploaded file named metal shoe back
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Paul from SWISCO responded:

Hello there!

Thank you for reaching out to us. I believe we can help with this though it must be a custom order due to the way your balance mounts. We'll use the Series 770 with a 27" metal channel and install a rivet in the top hole so that it can install with the 19-030 long S-clip (sold separately). The old knife lock shoe is discontinued though so you will need to reuse it and find a way to install it on the balance. We will also use the 27F stamp option. A pair of balances with this stamp will support a sash weighing 30 to 34 pounds but you could always weigh the window sash on a scale to confirm since custom orders are nonrefundable. 

With that said, I'll email you a purchase link and price quote for (2) balances that you can use to place an order on our website.

If you have any questions just let me know!

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