Channel balance

Hello,

With this combination of attachments, you could have either an S380-27 or S385-27 channel balance. You’ll need to measure as shown below. The Series 380 has a 1" bottom attachment, and the Series 385 has a 1-3/32" attachment. You'll also need 2640 spring strength options for your replacement balances.

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

Comparison of the S378, S380 and S385 balance shoes.

Great, as I mentioned in my original response, you'll need a 2640 spring strength option based on the stamp number shown in your photos. If you want to test it, you'll need to remove and weigh the window sash. There is a chart under our balance product description that will tell you what strength option you need based on the sash weight. Thank you!