SWISCO - The Replacement Hardware Authority

Stamped with 34 4 BX CMC 10

A contractor from Tallahassee, FL says:
This window balance spring came from a single hung window where each sash is 36 wide x 34 tall. The metal channel is 35" without the plastic ends and 35 3/4" with the plastic ends.
User submitted photos of a window balance.
Profile picture of Tom
Tom from SWISCO responded:
Hey, thanks for posting. I've narrowed this down to two possible channel balance Series: either our Series 380 or our Series 385 balances.

Now, as you can see, there is only one difference between these two Series, and that is their bottom shoe. The Series 380 uses the 15-005 while the Series 385 uses the 15-004. I can't quite tell what you have based on your pictures, though. Please carefully compare their dimensions to your own hardware and see which is a better match.
15-004 and 15-005
A contractor from FL says:
I have a third window in the house that needs 2 more balance springs. The code stamped on the spring is different. Can you tell enough based on what the previous springs were and the photo of the newest balance spring to determine which balance spring I will need for the next window?

Also, do you sell the little plastic clips that are attached to the sash and sit inside the channel to hold the window on top of the balance spring? What are they called so that I can find them on your site?


User submitted a photo of a window balance.
Profile picture of Paul
Paul from SWISCO responded:
I can see that your balance is 35" long and would have a stamp of 3450, but I do not know what Series it is. You will have to follow the instructions Tom posted above in order to find the right Series.

The nylon piece that is screwed on the top of your window sash is called top sash guide. You can see our entire selection by visiting this link.
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