Window channel balance

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. 

Based on your balance stamp, you'll also need 2640 spring strength options for your replacement balances but keep in mind that this strength option is for a sash between 19 and 26 lbs. If you're sure that your sash weight is exactly 17 pounds, you should go with the 2630 option for your balances. 

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

Comparison of the S378, S380 and S385 balance shoes.