Window balance

Hello,

You my be able to go with a 3040 option, but I would recommend removing and weighing your bottom sash to be sure. There is a chart below the product image that will tell you which option to choose based on your sash weight. 

Also, if you would like us to confirm that our S385-31 will work for you, I would recommend sending us a photo of the balance with both end attachments in view. Our S380 and S385 are almost identical besides the dimensions of the shoe. The Series 380 has a 1" bottom attachment, and the Series 385 has a 1-3/32" attachment. 

Thank you and let us know if you have any other questions or concerns.

Comparison of 15-004 and 15-005